Bump pa11y from 8.0.0 to 9.0.0

Bumps [pa11y](https://github.com/pa11y/pa11y) from 8.0.0 to 9.0.0.
- [Release notes](https://github.com/pa11y/pa11y/releases)
- [Changelog](https://github.com/pa11y/pa11y/blob/main/CHANGELOG.md)
- [Commits](pa11y/pa11y@8.0.0...9.0.0)

---
updated-dependencies:
- dependency-name: pa11y
  dependency-version: 9.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

package.json

@@ -20,7 +20,7 @@
   "homepage": "https://github.com/dwyl/tachyons-bootstrap#readme",
   "dependencies": {
     "http-server": "^14.1.0",
-    "pa11y": "^8.0.0",
+    "pa11y": "^9.0.0",
     "pre-commit": "^1.2.2"
   },
   "devDependencies": {