MSSQL Datasource: Revert functions within macros change (#63592)
* Revert functions within macros change
* Add tests for function and macro for mssql
* Remove macro support tests
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Co-authored-by: Oscar Kilhed <oscar.kilhed@grafana.com>
(cherry picked from commit 356e2e1933)
Co-authored-by: Kyle Cunningham <codeincarnate@users.noreply.github.com>