feat(eslint-plugin): [no-unsafe-member-access] report any typed computed prop access

[bradzacher]

Context: #791 (comment)

Simple enough.
Accessing using a property via a computed key which is typed as any is unsafe.
noImplicitAny actually catches this when accessing properties on object types, but it does not do the same check on arrays.

[typescript-eslint]

Thanks for the PR, @bradzacher!

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 #1683 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1683      +/-   ##
==========================================
+ Coverage   95.17%   95.17%   +<.01%     
==========================================
  Files         148      148              
  Lines        6938     6947       +9     
  Branches     1999     2002       +3     
==========================================
+ Hits         6603     6612       +9     
  Misses        124      124              
  Partials      211      211

Impacted Files	Coverage Δ
...eslint-plugin/src/rules/no-unsafe-member-access.ts	100% <100%> (ø)	⬆️