Log the root cause why git remote fetch python fails

[cmoulliard]

Issue

When this code fails then cachi2 reports such a message

step-prefetch-dependencies
INFO: Using mounted CA bundle: /mnt/trusted-ca/ca-bundle.crt
'/mnt/trusted-ca/ca-bundle.crt' -> '/etc/pki/ca-trust/source/anchors/ca-bundle.crt'
2024-10-15 12:49:16,848 DEBUG Testing for go mod file in /var/workdir/source/jam/go.mod
2024-10-15 12:49:16,848 DEBUG Testing for go mod file in /var/workdir/source/create-package/go.mod
2024-10-15 12:49:16,848 DEBUG Testing for go mod file in /var/workdir/source/pack/go.mod
2024-10-15 12:49:17,255 ERROR FetchError: Failed to fetch the tags on the Git repository (GitCommandError) for /var/workdir/source

which is missing why git failed. That will not help the users to figure out what they should do !
The root cause or stack trace should be logged. See hereafter:

Traceback (most recent call last):
  File "/var/workdir/source/.tekton/git-fetch.py", line 23, in fetch_git_tags
    repo.remote().fetch(force=True, tags=True)
  File "/venv/lib64/python3.9/site-packages/git/remote.py", line 1069, in fetch
    res = self._get_fetch_info_from_stderr(proc, progress, kill_after_timeout=kill_after_timeout)
  File "/venv/lib64/python3.9/site-packages/git/remote.py", line 895, in _get_fetch_info_from_stderr
    proc.wait(stderr=stderr_text)
  File "/venv/lib64/python3.9/site-packages/git/cmd.py", line 834, in wait
    raise GitCommandError(remove_password_if_present(self.args), status, errstr)
git.exc.GitCommandError: Cmd('git') failed due to: exit code(1)
  cmdline: git fetch -v --force --tags -- origin
  stderr: 'fatal: remote error: upload-pack: not our ref f06ea2185060f86690509c03faa793875bf0e221'
Current commit: 262cc4839eae9a07cd8ed0839ab33a15aad5f056
Failed to fetch the tags on the Git repository (GitCommandError) for /var/workdir/source

[eskultety]

Thank you for reporting this. This will likely be a problem spanning across multiple process executions, not strictly tied to just git so we need to apply a fix globally.