fix(eslint-plugin): [quotes] ignore backticks for Enum members

[a-tarasyuk]

Fixes #1351

[typescript-eslint]

Thanks for the PR, @a-tarasyuk!

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 #1355 into master will increase coverage by 0.03%.
The diff coverage is 88.88%.

@@            Coverage Diff             @@
##           master    #1355      +/-   ##
==========================================
+ Coverage      94%   94.04%   +0.03%     
==========================================
  Files         132      132              
  Lines        5874     5876       +2     
  Branches     1663     1661       -2     
==========================================
+ Hits         5522     5526       +4     
  Misses        186      186              
+ Partials      166      164       -2

Impacted Files	Coverage Δ
packages/eslint-plugin/src/rules/quotes.ts	94.11% <88.88%> (+14.11%)	⬆️

[bradzacher]

LGTM

One request while we're at it - could you please add the following:

• TSMethodSignature
• ClassProperty
• TSAbstractClassProperty
• TSAbstractMethodDefinition

I think that makes the complete set of property-like things that TS supports.
That way we won't have any future issues.

[a-tarasyuk]

@bradzacher Sure.

[bradzacher]

LGTM - thanks for doing this, and thanks for going the extra mile.