fix(eslint-plugin): [return-await] handle nested functions correctly

[MichaelBelousov]

fix for #3600

[typescript-eslint]

Thanks for the PR, @MichaelBelousov!

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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[nx-cloud]

Nx Cloud Report

CI ran the following commands for commit 8b1f4c5. Click to see the status, the terminal output, and the build insights.

📂 See all runs for this branch

Status	Command
	nx run-many --target=build --all --parallel
	nx run-many --target=typecheck --all --parallel

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Sent with 💌 from NxCloud.

[MichaelBelousov]

@bradzacher is the apparent Nx Cloud Report something that is blocking this PR?

[codecov]

Codecov Report

Merging #3601 (8b1f4c5) into master (f2c078c) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #3601      +/-   ##
==========================================
+ Coverage   92.64%   92.65%   +0.01%     
==========================================
  Files         326      326              
  Lines       11253    11255       +2     
  Branches     3171     3171              
==========================================
+ Hits        10425    10428       +3     
  Misses        368      368              
+ Partials      460      459       -1     

Flag	Coverage Δ
unittest	92.65% <100.00%> (+0.01%)	⬆️

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

Impacted Files	Coverage Δ
packages/eslint-plugin/src/rules/return-await.ts	96.96% <100.00%> (+1.09%)	⬆️

[MichaelBelousov]

@bradzacher sorry for bothering, but it's been silent so I don't know where we're at with this one. Is this slated for review?

[bradzacher]

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.

https://github.com/typescript-eslint/typescript-eslint/blob/master/CONTRIBUTING.md#addressing-feedback-and-beyond

[bradzacher]

LGTM - thanks for fixing this!