fix: downgrade postcss-safe-parser to v6 (#319)

* fix: downgrade postcss-safe-parser to v6

* Create bright-foxes-drop.md

Author: ota-meshi

Diff for: .changeset/bright-foxes-drop.md

@@ -0,0 +1,5 @@
+---
+"eslint-plugin-vue-scoped-css": patch
+---
+
+fix: downgrade postcss-safe-parser to v6

Diff for: .eslintrc.js

@@ -15,6 +15,7 @@ module.exports = {
     "plugin:@ota-meshi/+json",
     "plugin:@ota-meshi/+yaml",
     "plugin:@ota-meshi/+prettier",
+    "plugin:node-dependencies/recommended",
   ],
   rules: {
     "require-jsdoc": "error",