Bump @webref/css from 8.6.0 to 8.6.1 in the webref-css group

Bumps the webref-css group with 1 update: [@webref/css](https://github.com/w3c/webref).


Updates `@webref/css` from 8.6.0 to 8.6.1
- [Commits](https://github.com/w3c/webref/compare/@webref/css@8.6.0...@webref/css@8.6.1)

---
updated-dependencies:
- dependency-name: "@webref/css"
  dependency-version: 8.6.1
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: webref-css
...

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

Author: dependabot[bot]

package-lock.json

@@ -41,7 +41,7 @@
 		}
 	},
 	"devDependencies": {
-		"@webref/css": "^8.6.0",
+		"@webref/css": "^8.6.1",
 		"css-tree": "^3.2.1",
 		"postcss": "^8.5"
 	},

packages/css-syntax-patches-for-csstree/package.json

@@ -128,7 +128,7 @@
 		"@csstools/pack-test": "*",
 		"@csstools/postcss-bundler": "*",
 		"@csstools/postcss-tape": "*",
-		"@webref/css": "^8.6.0"
+		"@webref/css": "^8.6.1"
 	},
 	"scripts": {
 		"prebuild": "node ./scripts/generate-plugins-data.mjs && eslint --fix ./src/plugins/*.mjs",

plugin-packs/postcss-preset-env/package.json

@@ -38,7 +38,7 @@
 	},
 	"devDependencies": {
 		"@csstools/postcss-tape": "*",
-		"@webref/css": "^8.6.0"
+		"@webref/css": "^8.6.1"
 	},
 	"scripts": {
 		"build": "node ./scripts/matchers.mjs && node ./scripts/shorthands.mjs && eslint --fix ./src/matchers.ts ./src/shorthands.ts  && rollup -c ../../rollup/default.mjs",