fix(eslint-plugin): [method-signature-style] correct fixer for overloads in an object literal type

[a-tarasyuk]

Fixes #2706

[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!

---

🙏 Please, if you or your company is finding typescript-eslint valuable, help us sustain the project by sponsoring it transparently on https://opencollective.com/typescript-eslint. As a thank you, your profile/company logo will be added to our main README which receives thousands of unique visitors per day.

[codecov]

Codecov Report

Merging #2708 into master will decrease coverage by 0.01%.
The diff coverage is 57.14%.

@@            Coverage Diff             @@
##           master    #2708      +/-   ##
==========================================
- Coverage   92.78%   92.76%   -0.02%     
==========================================
  Files         295      295              
  Lines        9712     9716       +4     
  Branches     2725     2727       +2     
==========================================
+ Hits         9011     9013       +2     
  Misses        331      331              
- Partials      370      372       +2     

Flag	Coverage Δ
#unittest	92.76% <57.14%> (-0.02%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
.../eslint-plugin/src/rules/method-signature-style.ts	87.20% <57.14%> (-1.82%)	⬇️

[bradzacher]

LGTM - thanks for fixing this!