test: use newer version of Electron

[erickzhao]

Upgrades to the latest Electron stable release. Fixes tests not working on macOS arm64 machines since Electron 2 did not support Apple silicon.

[codecov]

Codecov Report

Merging #145 (57c7919) into main (b935f64) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #145   +/-   ##
=======================================
  Coverage   75.43%   75.43%           
=======================================
  Files           1        1           
  Lines          57       57           
=======================================
  Hits           43       43           
  Misses         14       14           

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