fix(eslint-plugin): [no-shadow] ignore global module augmentation

[cherryblossom000]

Fixes #2724

[typescript-eslint]

Thanks for the PR, @cherryblossom000!

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 #2729 into master will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #2729   +/-   ##
=======================================
  Coverage   92.75%   92.75%           
=======================================
  Files         296      296           
  Lines        9739     9744    +5     
  Branches     2733     2735    +2     
=======================================
+ Hits         9033     9038    +5     
  Misses        332      332           
  Partials      374      374           

Flag	Coverage Δ
unittest	92.75% <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/no-shadow.ts	94.04% <100.00%> (+0.37%)	⬆️

[bradzacher]

thanks!