fix(template/typescript-webpack): magic constant is a string & describe it

[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 are appropriately documented (if applicable).

Summarize your changes:

Does what it says on the tin.

[codecov]

Codecov Report

Merging #2166 (738c406) into master (90f122c) will decrease coverage by 16.40%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           master    #2166       +/-   ##
===========================================
- Coverage   72.71%   56.31%   -16.41%     
===========================================
  Files          74       47       -27     
  Lines        2221     1442      -779     
  Branches      420      290      -130     
===========================================
- Hits         1615      812      -803     
- Misses        446      531       +85     
+ Partials      160       99       -61     

Impacted Files	Coverage Δ
packages/api/core/src/util/upgrade-forge-config.ts	10.71% <0.00%> (-85.72%)	⬇️
packages/api/core/src/util/publish-state.ts	12.19% <0.00%> (-80.49%)	⬇️
packages/maker/dmg/src/MakerDMG.ts	38.88% <0.00%> (-61.12%)	⬇️
packages/api/core/src/util/electron-version.ts	33.33% <0.00%> (-60.32%)	⬇️
packages/maker/deb/src/MakerDeb.ts	42.10% <0.00%> (-57.90%)	⬇️
packages/maker/rpm/src/MakerRpm.ts	42.10% <0.00%> (-57.90%)	⬇️
packages/api/core/src/api/publish.ts	18.42% <0.00%> (-51.32%)	⬇️
packages/api/core/src/util/hook.ts	40.00% <0.00%> (-50.00%)	⬇️
packages/maker/wix/src/util/author-name.ts	50.00% <0.00%> (-50.00%)	⬇️
packages/maker/appx/src/util/author-name.ts	50.00% <0.00%> (-50.00%)	⬇️
... and 55 more

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