chore(deps): update devdependency eslint to v8.21.0

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
eslint (source)	8.20.0 -> 8.21.0

---

Release Notes

eslint/eslint

v8.21.0

Compare Source

Features

• 7b43ea1 feat: Implement FlatESLint (#​16149) (Nicholas C. Zakas)
• 92bf49a feat: improve the key width calculation in key-spacing rule (#​16154) (Nitin Kumar)
• c461542 feat: add new allowLineSeparatedGroups option to the sort-keys rule (#​16138) (Nitin Kumar)
• 1cdcbca feat: add deprecation warnings for legacy API in RuleTester (#​16063) (Nitin Kumar)

Bug Fixes

• 0396775 fix: lines-around-comment apply allowBlockStart for switch statements (#​16153) (Nitin Kumar)

Documentation

• 2aadc93 docs: add anchors to headings inside docs content (#​16134) (Strek)

Chores

• 8892511 chore: Upgrade to Espree 9.3.3 (#​16173) (Brandon Mills)
• 1233bee chore: switch to eslint-plugin-node's maintained fork (#​16150) (唯然)
• 97b95c0 chore: upgrade puppeteer v13 (#​16151) (唯然)

---

Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Enabled.

♻ Rebasing: Whenever PR is behind base branch, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

---

• If you want to rebase/retry this PR, click this checkbox.

---

This PR has been generated by Mend Renovate. View repository job log here.

[codecov]

Codecov Report

Merging #126 (7d94eb1) into main (9659e9e) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##              main      #126   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            1         1           
  Lines           10        10           
  Branches         1         1           
=========================================
  Hits            10        10           

Help us with your feedback. Take ten seconds to tell us how you rate us.