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]

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 ⚠️
...skDetails/ActiveTaskControls/ActiveTaskControls.js	0.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            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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