Merge pull request #577 from C-Lodder/dependabot/npm_and_yarn/postcss-mixins-12.0.0

Bump postcss-mixins from 11.0.3 to 12.0.0

Author: C-Lodder

package-lock.json

@@ -27,7 +27,7 @@
     "postcss-discard-comments": "^7.0.4",
     "postcss-each": "^1.1.0",
     "postcss-easy-import": "^4.0.0",
-    "postcss-mixins": "^11.0.3",
+    "postcss-mixins": "^12.0.0",
     "postcss-nested": "^6.2.0",
     "stylelint": "^15.10.3",
     "stylelint-config-standard": "^34.0.0",