fix(eslint-plugin): fix false positives for adjacent-overload-signatures regarding computed property names

[uniqueiniquity]

Currently, the name of a method definition or a class property is always assumed to be a literal or an identifier. However, this fails to account for computed property names.
In those cases, we currently sometimes give the name for a method definition with a computed name as undefined, which as a result causes methods with differing computed property names to be marked as overloads of each other. In this PR, we slice the text of the computed property name out to handle these cases.

[codecov]

Codecov Report

Merging #340 into master will decrease coverage by 0.03%.
The diff coverage is 90.9%.

@@            Coverage Diff             @@
##           master     #340      +/-   ##
==========================================
- Coverage   97.27%   97.24%   -0.04%     
==========================================
  Files          67       67              
  Lines        2348     2357       +9     
  Branches      335      336       +1     
==========================================
+ Hits         2284     2292       +8     
- Misses         43       44       +1     
  Partials       21       21

Impacted Files	Coverage Δ
packages/eslint-plugin/src/rules/member-naming.ts	100% <100%> (ø)	⬆️
...-plugin/src/rules/explicit-member-accessibility.ts	100% <100%> (ø)	⬆️
...ackages/eslint-plugin/src/rules/member-ordering.ts	96.72% <100%> (+0.05%)	⬆️
...t-plugin/src/rules/adjacent-overload-signatures.ts	94.44% <100%> (+0.15%)	⬆️
packages/eslint-plugin/src/util/misc.ts	80% <80%> (ø)	⬆️

[bradzacher]

LGTM