Bugfix: apply http.sslVerify to the current Git command only

[SSE4]

Changelog: Bugfix: apply http.sslVerify to the current Git command only
Docs: omit
closes: #5462
@tags: slow, svn

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^{Note: By default this PR will skip the slower tests and will use a limited set of python versions. Check here how to increase the testing level by writing some tags in the current PR body text.}