build(deps): bump stylelint from 15.5.0 to 15.6.0 (#1545)

Bumps [stylelint](https://github.com/stylelint/stylelint) from 15.5.0 to 15.6.0.
- [Release notes](https://github.com/stylelint/stylelint/releases)
- [Changelog](https://github.com/stylelint/stylelint/blob/main/CHANGELOG.md)
- [Commits](stylelint/stylelint@15.5.0...15.6.0)

---
updated-dependencies:
- dependency-name: stylelint
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

package.json

@@ -107,7 +107,7 @@
     "sinon-chrome": "^3.0.1",
     "snowpack": "^3.8.8",
     "snowpack-plugin-replace": "^1.0.4",
-    "stylelint": "^15.5.0",
+    "stylelint": "^15.6.0",
     "stylelint-config-standard": "^33.0.0",
     "stylelint-order": "^6.0.3",
     "ts-lit-plugin": "^1.2.1",