feat: BB datacenter/server support

[fuskovic]

Closes: #6020

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[codecov]

Codecov Report

❌ Patch coverage is 97.62846% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 58.54%. Comparing base (4afa565) to head (1778923).
⚠️ Report is 103 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/gitprovider/bitbucket/datacenter/provider.go	97.62%	4 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6128      +/-   ##
==========================================
+ Coverage   58.30%   58.54%   +0.24%     
==========================================
  Files         500      501       +1     
  Lines       41925    42178     +253     
==========================================
+ Hits        24444    24693     +249     
- Misses      16012    16015       +3     
- Partials     1469     1470       +1     

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[krancour]

I think there are some things to discuss here still, but I am really happy to see that generating a BB client and using that appears tenable.

[fuskovic]

@krancour so far we are able to:

1. Remove github.com/ktrysmt/go-bitbucket
2. Support Datacenter/Server
3. Support alternative merge strategies for both

This obviously needs a lot of end-to-end testing.

Per our offline discussion I have sub-packages:

• pkg/gitprovider/bitbucket/cloud
• pkg/gitprovider/bitbucket/datacenter

Implemented each with their own individual registration predicate.

[fuskovic]

I can take this out of draft and start end-to-end testing unless there's something else we still want to discuss?

[fuskovic]

To unblock non-server/datacenter work, bb cloud client gen and alt merge strategy support have been moved into a separate PR here.

Will leave this open for now in the event we are unblocked on testing the datacenter path in the future.