fix(eslint-plugin): [consistent-type-imports] incorrect handling of computed property type signatures

[bradzacher]

Fixes #2989

[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 #2990 (dca2f8e) into master (7b701a3) will decrease coverage by 0.02%.
The diff coverage is 85.18%.

@@            Coverage Diff             @@
##           master    #2990      +/-   ##
==========================================
- Coverage   92.74%   92.71%   -0.03%     
==========================================
  Files         313      313              
  Lines       10639    10655      +16     
  Branches     3018     3018              
==========================================
+ Hits         9867     9879      +12     
- Misses        353      355       +2     
- Partials      419      421       +2     

Flag	Coverage Δ
unittest	92.71% <85.18%> (-0.03%)	⬇️

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

Impacted Files	Coverage Δ
...eslint-plugin/src/rules/consistent-type-imports.ts	93.64% <85.18%> (-1.36%)	⬇️