fix(eslint-plugin): typedef shouldn't flag destructurings when variables are disabled

[JoshuaKGoldberg]

Fixes #788.

[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 #819 into master will decrease coverage by <.01%.
The diff coverage is 91.66%.

@@            Coverage Diff             @@
##           master     #819      +/-   ##
==========================================
- Coverage   94.08%   94.07%   -0.01%     
==========================================
  Files         113      113              
  Lines        4917     4914       -3     
  Branches     1370     1369       -1     
==========================================
- Hits         4626     4623       -3     
  Misses        165      165              
  Partials      126      126

Impacted Files	Coverage Δ
packages/eslint-plugin/src/rules/typedef.ts	95.65% <91.66%> (-0.27%)	⬇️

[bradzacher]

thanks for this!

[octogonz]

Thanks for fixing this!