[Dependency] Bump RainbowGrades from v23.07.01 to v23.09.00

[SubmittyBot]

Bumps RainbowGrades from v23.07.01 to v23.09.00.

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See release notes

[codecov]

Codecov Report

Merging #9770 (5298928) into main (4847ddc) will not change coverage.
Report is 1 commits behind head on main.
The diff coverage is n/a.

❗ Current head 5298928 differs from pull request most recent head 1e04cd7. Consider uploading reports for the commit 1e04cd7 to get more accurate results

@@            Coverage Diff            @@
##               main    #9770   +/-   ##
=========================================
  Coverage     23.25%   23.25%           
  Complexity     8232     8232           
=========================================
  Files           227      227           
  Lines         29362    29362           
  Branches         73       73           
=========================================
  Hits           6828     6828           
  Misses        22464    22464           
  Partials         70       70           

Flag	Coverage Δ
autograder	22.15% <ø> (ø)
js	27.51% <ø> (ø)
migrator	100.00% <ø> (ø)
php	20.15% <ø> (ø)
python_submitty_utils	71.65% <ø> (ø)
submitty_daemon_jobs	91.01% <ø> (ø)

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