Fix #646: Upgrade electron to 27.0.3

[araujoarthur0]

Related issue

Closes #646

Context / Background

Updating electron to a newer version than 12 :)

What change is being introduced by this PR?

• Electron 12 made contextIsolation: true by default.
  • Had to update our jest patch in order to disable contextIsolation on renderer tests, otherwise the require() statements would stop working.
• Electron 14 removed the electron.remote module
  • Had to replace our usage in the code with the new package @electron/remote. This requires initialization in main process, which for renderer tests is done in the jest rpc patch.
  • The electron-store package v6 stopped working because it required the old remote. Upgrade to latest, which now requires an initialization step in main just like above.
• Electron 25 broke the schema for the Event in Notification.
  • This is not considered a breaking change because the schema was not publicly documented, and we used the sender member in our tests, which went away. Had to remove the line in the tests.
• Removed a few unused dependencies as well.

How will this be tested?

Ran the app locally, all tests are also passing.
Also testing the release flow in https://github.com/araujoarthur0/time-to-leave/actions/runs/6745696311

[codecov]

Codecov Report

Merging #1035 (aab44ac) into main (3f7076e) will increase coverage by 4.34%.
Report is 4 commits behind head on main.
The diff coverage is 25.58%.

@@            Coverage Diff             @@
##             main    #1035      +/-   ##
==========================================
+ Coverage   75.02%   79.37%   +4.34%     
==========================================
  Files          26       21       -5     
  Lines        2202     1275     -927     
  Branches      346      189     -157     
==========================================
- Hits         1652     1012     -640     
+ Misses        550      263     -287     

Files	Coverage Δ
js/time-balance.js	100.00% <ø> (ø)
js/user-preferences.js	100.00% <100.00%> (ø)
js/window-aux.js	100.00% <100.00%> (ø)
js/main-window.js	73.50% <87.50%> (+0.46%)	⬆️
js/menus.js	81.73% <50.00%> (ø)
src/calendar.js	0.00% <0.00%> (ø)

... and 4 files with indirect coverage changes

[tupaschoal]

I did some testing and it all seems to be working great, a 16 major version jump is no small feat, thanks @araujoarthur0 !

[araujoarthur0]

\changelog-update
Message: Enhancement [#646]: Title bar color now follows Windows mode (dark or light)