fix: close modal using the esc key after pressing other keys

[brenopolanski]

Summary

Fixes #1827.

The once property in addEventListener has been removed because if true, the listener would be automatically removed when invoked.

The keyCode is deprecated: https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/keyCode

The problem with using keyCode is that non-English keyboards can produce different outputs and even keyboards with different layouts can produce inconsistent results.

Checklist

• Documentation (if necessary)
• Tests (if necessary)
• Ready to be merged

[codecov]

Codecov Report

Merging #1828 into develop will not change coverage.
The diff coverage is 50%.

@@           Coverage Diff            @@
##           develop    #1828   +/-   ##
========================================
  Coverage    60.15%   60.15%           
========================================
  Files          369      369           
  Lines         9142     9142           
  Branches      1869     1869           
========================================
  Hits          5499     5499           
  Misses        3458     3458           
  Partials       185      185

Impacted Files	Coverage Δ
src/renderer/components/Modal/ModalWindow.vue	77.27% <50%> (ø)	⬆️

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