fix: adding support for dynamic mounting dir

[ChiefHolland]

Contributor Comments

This PR fixes a bug in setting the top level directory for GIT_CONFIG_VALUE_0, which is used to mark a git directory as "safe."
The conditional to set this env was git rev-parse --show-toplevel > /dev/null || /iac.
When mounting a working dir that is different from /iac and encountering an error with git rev-parse, the base dir was incorrectly assigned "/iac." This caused logging git-related information to fail because git would detect "dubious ownership" of a directory not marked "safe."
The fix is to make the 'or' condition dynamic to the mounted volume path.

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[JonZeolla]

One minor var naming item. Also please update a test to exercise this feature and demonstrate how it used to fail and now passes with links to Passing and failing pipelines