fix: shuup/notify/package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-POSTCSS-1090595

shuup/notify/package.json

@@ -17,11 +17,11 @@
     "@babel/cli": "7.12.7",
     "@babel/core": "7.12.7",
     "@babel/preset-env": "7.12.7",
-    "autoprefixer": "^9.6.1",
+    "autoprefixer": "^10.0.0",
     "babel-preset-env": "^1.7.0",
     "less": "^3.0.4",
     "parcel-bundler": "^1.12.4",
-    "postcss-modules": "^1.1.0",
+    "postcss-modules": "^4.0.0",
     "shuup-static-build-tools": "^1.0.3"
   },
   "devDependencies": {