fix(eslint-plugin): [explicit-module-boundary-types] dont report return type errors on constructor overloads

[bradzacher]

Fixes #2150

[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 #2158 into master will decrease coverage by 0.00%.
The diff coverage is 50.00%.

@@            Coverage Diff             @@
##           master    #2158      +/-   ##
==========================================
- Coverage   93.55%   93.54%   -0.01%     
==========================================
  Files         171      171              
  Lines        7799     7812      +13     
  Branches     2225     2230       +5     
==========================================
+ Hits         7296     7308      +12     
  Misses        244      244              
- Partials      259      260       +1     

Flag	Coverage Δ
#unittest	93.54% <50.00%> (-0.01%)	⬇️

Impacted Files	Coverage Δ
...plugin/src/rules/explicit-module-boundary-types.ts	89.23% <50.00%> (-0.70%)	⬇️
...slint-plugin/src/rules/no-unnecessary-condition.ts	97.26% <0.00%> (+0.24%)	⬆️