fix(eslint-plugin): [no-dynamic-delete] prevent fixing to identifiers

[a-tarasyuk]

Fixing #1240

[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 #1244 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1244      +/-   ##
==========================================
- Coverage   94.23%   94.23%   -0.01%     
==========================================
  Files         126      126              
  Lines        5379     5377       -2     
  Branches     1511     1510       -1     
==========================================
- Hits         5069     5067       -2     
  Misses        177      177              
  Partials      133      133

Impacted Files	Coverage Δ
...kages/eslint-plugin/src/rules/no-dynamic-delete.ts	100% <100%> (ø)	⬆️

[bradzacher]

LGTM - thanks for this