refactor: replace indexOf with includes/startsWith where applicable

[malept]

• I have read the contribution documentation for this project.
• I agree to follow the code of conduct that this project follows, as appropriate.
• The changes have sufficient test coverage (if applicable).
• The testsuite passes successfully on my local machine (if applicable).

Summarize your changes:

This is a more complete version of #1305.

Closes #1305.

[codecov]

Codecov Report

Merging #1337 into master will increase coverage by 0.6%.
The diff coverage is 0%.

@@            Coverage Diff            @@
##           master    #1337     +/-   ##
=========================================
+ Coverage   68.28%   68.89%   +0.6%     
=========================================
  Files          70       70             
  Lines        2040     2038      -2     
  Branches      383      382      -1     
=========================================
+ Hits         1393     1404     +11     
+ Misses        473      459     -14     
- Partials      174      175      +1

Impacted Files	Coverage Δ
packages/api/core/src/api/publish.ts	75.32% <ø> (ø)	⬆️
packages/api/core/src/api/make.ts	70.78% <0%> (+5.61%)	⬆️
packages/plugin/webpack/src/WebpackPlugin.ts	30.67% <0%> (+0.25%)	⬆️
packages/api/core/src/api/install.ts	79.74% <0%> (ø)	⬆️
packages/api/core/src/api/import.ts	58.41% <0%> (ø)	⬆️
packages/maker/dmg/src/MakerDMG.ts	100% <0%> (+5.55%)	⬆️
packages/api/core/src/util/electron-version.ts	96.07% <0%> (+7.84%)	⬆️
packages/maker/zip/src/MakerZIP.ts	100% <0%> (+9.09%)	⬆️

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