docs: fix collapse summary truncation

[woutdenolf]

The problem: doc build fails

CI is currently broken. make local is failing because the collapse-summary truncationlong_doc() in dev_tools/docs/nxdl.py, currently a blind single_line[:max_characters] slice, is cutting doc text mid RST inline-markup.

Examples:

Traceback

This produces 28 docutils warnings (fatal under -W) and one Unknown target name error.

Errors regarding "start-string without end-string" due to truncation...

/home/runner/work/definitions/definitions/build/manual/source/classes/applications/NXapm.rst:2517: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/applications/NXcanSAS.rst:1569: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/applications/NXmpes.rst:335: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/applications/NXmpes.rst:434: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/applications/NXmpes_arpes.rst:690: WARNING: Inline literal start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/applications/NXmx.rst:579: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/applications/NXmx.rst:621: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/applications/NXstress.rst:1205: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/applications/NXstress.rst:1494: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/applications/NXstress.rst:1527: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/applications/NXxeuler.rst:20: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/base_classes/NXapm_charge_state_analysis.rst:84: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/base_classes/NXatom.rst:247: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/base_classes/NXcalibration.rst:172: WARNING: Inline literal start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/base_classes/NXdata.rst:315: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/base_classes/NXdata.rst:419: WARNING: Inline literal start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/base_classes/NXdata.rst:522: WARNING: Inline literal start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/base_classes/NXdetector_module.rst:132: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/base_classes/NXfit.rst:145: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/base_classes/NXfit.rst:203: WARNING: Inline literal start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/base_classes/NXimage.rst:103: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/contributed_definitions/NXapm_paraprobe_nanochem_config.rst:403: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/contributed_definitions/NXmicrostructure_ipf.rst:50: ERROR: Unknown target name: "axis". [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/contributed_definitions/NXmicrostructure_odf.rst:166: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/contributed_definitions/NXmicrostructure_score_config.rst:758: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/contributed_definitions/NXregion.rst:119: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/contributed_definitions/NXsolid_geometry.rst:57: WARNING: Inline interpreted text or phrase reference start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/contributed_definitions/NXxpcs.rst:392: WARNING: Inline literal start-string without end-string. [docutils]
/home/runner/work/definitions/definitions/build/manual/source/classes/contributed_definitions/NXxpcs.rst:486: WARNING: Inline literal start-string without end-string. [docutils]

The solution: fix long_doc truncation

This PR strips the partial RST inline-markups.

Examples:

[woutdenolf]

FYI @PeterC-DLS the CI of several PRs is broken. This seems to fix it. Not sure why this was not a problem before.