chore: enable no-unsafe-return internally

[JoshuaKGoldberg]

Continues #3278.

no-unsafe-member-access had no violations. It had a bunch!

[typescript-eslint]

Thanks for the PR, @JoshuaKGoldberg!

typescript-eslint is a 100% community driven project, and we are incredibly grateful that you are contributing to that community.

The core maintainers work on this in their personal time, so please understand that it may not be possible for them to review your work immediately.

Thanks again!

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[codecov]

Codecov Report

Merging #3471 (68778c8) into master (15f7184) will decrease coverage by 0.01%.
The diff coverage is 91.66%.

❗ Current head 68778c8 differs from pull request most recent head c6a6a1f. Consider uploading reports for the commit c6a6a1f to get more accurate results

@@            Coverage Diff             @@
##           master    #3471      +/-   ##
==========================================
- Coverage   92.64%   92.63%   -0.02%     
==========================================
  Files         326      325       -1     
  Lines       11253    11317      +64     
  Branches     3171     3193      +22     
==========================================
+ Hits        10425    10483      +58     
- Misses        368      370       +2     
- Partials      460      464       +4     

Flag	Coverage Δ
unittest	92.63% <91.66%> (-0.02%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
packages/eslint-plugin/src/configs/all.ts	100.00% <ø> (ø)
packages/typescript-estree/src/convert.ts	98.27% <ø> (ø)
...eslint-plugin/src/rules/prefer-return-this-type.ts	90.47% <90.47%> (ø)
...es/eslint-plugin/src/rules/no-loss-of-precision.ts	91.66% <100.00%> (ø)
packages/eslint-plugin/src/util/astUtils.ts	89.47% <100.00%> (+7.65%)	⬆️
packages/visitor-keys/src/get-keys.ts
packages/visitor-keys/src/visitor-keys.ts

[nx-cloud]

Nx Cloud Report

CI ran the following commands for commit c6a6a1f. Click to see the status, the terminal output, and the build insights.

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Status	Command
	nx run-many --target=build --all --parallel
	nx run-many --target=typecheck --all --parallel
	nx test @typescript-eslint/eslint-plugin
	nx test @typescript-eslint/eslint-plugin-internal
	nx test @typescript-eslint/eslint-plugin-tslint
	nx test @typescript-eslint/experimental-utils
	nx test @typescript-eslint/parser
	nx test @typescript-eslint/scope-manager
	nx test @typescript-eslint/typescript-estree
	nx test @typescript-eslint/visitor-keys

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