fix(eslint-plugin): [unbound-method] false positive on property function initializer

[greyscaled]

resolves #1869

[typescript-eslint]

Thanks for the PR, @vapurrmaid!

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 #1890 into master will decrease coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #1890      +/-   ##
==========================================
- Coverage   94.39%   94.38%   -0.02%     
==========================================
  Files         164      164              
  Lines        7583     7585       +2     
  Branches     2179     2180       +1     
==========================================
+ Hits         7158     7159       +1     
- Misses        182      183       +1     
  Partials      243      243              

Flag	Coverage Δ
#unittest	94.38% <100.00%> (-0.02%)	⬇️

Impacted Files	Coverage Δ
packages/eslint-plugin/src/rules/unbound-method.ts	95.23% <100.00%> (-1.49%)	⬇️

[bradzacher]

logic itself looks good.
one minor change

thanks for this!

[bradzacher]

nice! thanks for this

[markfields]

Thanks @vapurrmaid!