fix: determine the suitable github api base url from repo url

[chengfang]

Fix the issue raised in discussion #1038

When the github enterprise api base url is not set, try to determine it based on repo url.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 63.63%. Comparing base (74a3001) to head (e477659).
Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1058      +/-   ##
==========================================
+ Coverage   63.37%   63.63%   +0.26%     
==========================================
  Files          15       15              
  Lines        2326     2343      +17     
==========================================
+ Hits         1474     1491      +17     
  Misses        760      760              
  Partials       92       92              

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[jannfis]

Since we tend to copy over the Git client's code from Argo CD in a more or less verbatim way, and then enrich it with code in writer.go, is there any possibility that we could outsource these changes into a separate file?

[chengfang]

Shall we move the added func to a new file like creds2.go and test to creds2_test.go, or move it to the existing writer.go to avoid adding 2 short new files?

[chengfang]

Okay, I moved g.getBaseUrl() to a separate file creds2.go and test to creds2_test.go to minimize changing creds.go

[chengfang]

Will look into how to fix it in argo-cd instead.