fix(template-typescript-webpack): lint tsx files by default

[malept]

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• The changes have sufficient test coverage (if applicable).
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Summarize your changes:

Fixes electron-forge/electron-forge-docs#41

[codecov]

Codecov Report

Merging #2403 (228bcb5) into master (403b5f9) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #2403   +/-   ##
=======================================
  Coverage   75.03%   75.03%           
=======================================
  Files          91       91           
  Lines        2339     2339           
  Branches      437      437           
=======================================
  Hits         1755     1755           
  Misses        476      476           
  Partials      108      108           

Impacted Files	Coverage Δ
...ypescript-webpack/src/TypeScriptWebpackTemplate.ts	100.00% <100.00%> (ø)

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