fix empy mr tag bug

[CollinBeczak]

Issue: An empty mr tag was being added on task completion whenever a task was submitted without any mr tags.

This pr solves that issue by preventing a null value from being passed the endpoint that saves tags. Before fix:

After fix:

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 0% with 4 lines in your changes missing coverage. Please review.

Project coverage is 23.37%. Comparing base (95dca9d) to head (e997d23). Report is 6 commits behind head on main.

Files with missing lines	Patch %	Lines
...omponents/ReviewTaskControls/ReviewTaskControls.js	0.00%	1 Missing and 1 partial :warning:
...skDetails/ActiveTaskControls/ActiveTaskControls.js	0.00%	1 Missing and 1 partial :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #2413 +/- ## ========================================== - Coverage 23.38% 23.37% -0.01% ========================================== Files 649 649 Lines 22514 22515 +1 Branches 6902 6918 +16 ========================================== Hits 5264 5264 + Misses 14425 14424 -1 - Partials 2825 2827 +2 ```

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