chore(deps-dev): bump postcss-html from 1.7.0 to 1.8.1 in /web

Bumps [postcss-html](https://github.com/ota-meshi/postcss-html) from 1.7.0 to 1.8.1.
- [Release notes](https://github.com/ota-meshi/postcss-html/releases)
- [Commits](ota-meshi/postcss-html@v1.7.0...v1.8.1)

---
updated-dependencies:
- dependency-name: postcss-html
  dependency-version: 1.8.1
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

web/package.json

@@ -76,7 +76,7 @@
     "jest": "^30.2.0",
     "lint-staged": "^16.1.4",
     "node-fetch-native": "^1.6.7",
-    "postcss-html": "^1.7.0",
+    "postcss-html": "^1.8.1",
     "prettier": "3.8.1",
     "stylelint": "^15.11.0",
     "stylelint-config-prettier": "^9.0.5",