Replace legacy variable in dotNET CI template

Leaminn Marequested to merge
lma-git-master-patch-16050 into master

What does this MR do and why?

Replaces CI_BUILD_TAG with CI_COMMIT_TAG, as the former is getting removed. See https://docs.gitlab.com/ee/update/deprecations.html#ci_build_-predefined-variables

We are currently rolling out a feature flag that removes this legacy variable: [Feature flag] Roll out `ci_remove_legacy_prede... (#404533 - closed)

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

Edited by Leaminn Ma

Merge request reports