CompatHelper: bump compat for Electron to 4, (keep existing compat)

[github-actions]

This pull request changes the compat entry for the Electron package from 3.1 to 3.1, 4.
This keeps the compat entries for earlier versions.

Note: I have not tested your package with this new compat entry.
It is your responsibility to make sure that your package tests pass before you merge this pull request.

[codecov]

Codecov Report

Merging #907 (722f2d7) into master (795661a) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #907   +/-   ##
=======================================
  Coverage   84.56%   84.56%           
=======================================
  Files          40       40           
  Lines        3881     3881           
=======================================
  Hits         3282     3282           
  Misses        599      599           

Flag	Coverage Δ
unittests	84.56% <ø> (ø)

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