chore(deps): update dependency postcss to v8.5.9 (#2830)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

webclient/package.json

@@ -47,7 +47,7 @@
 		"@vue/tsconfig": "0.9.1",
 		"autoprefixer": "10.4.27",
 		"openapi-typescript": "6.7.6",
-		"postcss": "8.5.8",
+		"postcss": "8.5.9",
 		"tailwindcss": "3.4.19",
 		"typescript": "5.9.3",
 		"vue-tsc": "3.2.6"