[Chore] Fix symlinks test on Windows Git Bash

[aeqz]

Description

The current Windows CI started to fail at some point because it is running within an environment in which symlinks don't work properly.

Having symlinks working on Windows Git Bash has some requirements:

• Enable symlinks during git for windows installation, which is already met.
• Be either running as an admin or having Windows developer mode turned on, which is also already met.
• Use an environment variable to properly enable symlinks, which is being added with this PR.

Related issue(s)

None

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