nie można usunąć gałęzi sprawdzonej pod adresem

Switch to some other branch and delete Test_Branch, as follows:

$ git checkout master
$ git branch -d Test_Branch
If above command gives you error - The branch 'Test_Branch' is not fully merged. If you are sure you want to delete it and still you want to delete it, then you can force delete it using -D instead of -d, as:

$ git branch -D Test_Branch
To delete Test_Branch from remote as well, execute:

git push origin --delete Test_Branch
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