fix(eslint-plugin): [quotes] false positive with backtick in import equals statement

[regevbr]

Fixes #1766

[typescript-eslint]

Thanks for the PR, @regevbr!

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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[bradzacher]

ezpz.
thanks for this!

[codecov]

Codecov Report

Merging #1769 into master will not change coverage by %.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1769   +/-   ##
=======================================
  Coverage   95.19%   95.19%           
=======================================
  Files         148      148           
  Lines        6971     6971           
  Branches     2010     2010           
=======================================
  Hits         6636     6636           
  Misses        124      124           
  Partials      211      211           

Flag	Coverage Δ
#unittest	95.19% <ø> (ø)

Impacted Files	Coverage Δ
packages/eslint-plugin/src/rules/quotes.ts	94.11% <ø> (ø)