Bump postcss-custom-properties from 9.1.1 to 10.0.0

Bumps [postcss-custom-properties](https://github.com/csstools/postcss-plugins/tree/HEAD/plugins/postcss-custom-properties) from 9.1.1 to 10.0.0.
- [Changelog](https://github.com/csstools/postcss-plugins/blob/main/plugins/postcss-custom-properties/CHANGELOG.md)
- [Commits](https://github.com/csstools/postcss-plugins/commits/HEAD/plugins/postcss-custom-properties)

---
updated-dependencies:
- dependency-name: postcss-custom-properties
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

package-lock.json

@@ -43,7 +43,7 @@
     "js-yaml": "~3.13",
     "merge-stream": "~2.0",
     "postcss-calc": "~7.0",
-    "postcss-custom-properties": "~9.1",
+    "postcss-custom-properties": "~10.0",
     "postcss-import": "~12.0",
     "postcss-url": "~8.0",
     "prettier-eslint": "~9.0",