fix migration for user defined themes

[adelowo]

Fixes #5681

Friendly ping @wyattoday @kimpenhaus

[codecov-io]

Codecov Report

❗ No coverage uploaded for pull request base (master@2b36bdd). Click here to learn what that means.
The diff coverage is 0%.

@@            Coverage Diff            @@
##             master    #5682   +/-   ##
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  Coverage          ?   37.75%           
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  Files             ?      323           
  Lines             ?    47596           
  Branches          ?        0           
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  Hits              ?    17972           
  Misses            ?    27034           
  Partials          ?     2590

Impacted Files	Coverage Δ
models/migrations/v77.go	0% <0%> (ø)

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[allenh1]

Is there a way I can work around this temporarily (while this is getting merged)?

[kimpenhaus]

You can try and make an update to the SQL table user and set theme to empty string (or gitea or arc-green).