refactor: migrate templates from using tslint to eslint

[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:

Last year, it was declared that tslint was going to be deprecated in favor of eslint: https://eslint.org/blog/2019/01/future-typescript-eslint

As of tslint v6.0.0, it has been marked as deprecated: https://www.npmjs.com/package/tslint/v/6.0.0

This PR updates the templates to use the recommended linter, eslint.

[codecov]

Codecov Report

Merging #1467 into master will decrease coverage by 0.09%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master    #1467     +/-   ##
=========================================
- Coverage   75.16%   75.07%   -0.1%     
=========================================
  Files          73       73             
  Lines        2130     2130             
  Branches      397      397             
=========================================
- Hits         1601     1599      -2     
- Misses        407      409      +2     
  Partials      122      122

Impacted Files	Coverage Δ
...ypescript-webpack/src/TypeScriptWebpackTemplate.ts	100% <100%> (ø)	⬆️
...ages/template/typescript/src/TypeScriptTemplate.ts	100% <100%> (ø)	⬆️

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