Bump autoprefixer from 10.3.6 to 10.3.7 in /assets (#288)

Author: dependabot[bot]

assets/package-lock.json

@@ -11,7 +11,7 @@
   },
   "dependencies": {
     "alpinejs": "^3.4.2",
-    "autoprefixer": "^10.3.6",
+    "autoprefixer": "^10.3.7",
     "nprogress": "^0.2.0",
     "phoenix": "file:../deps/phoenix",
     "phoenix_html": "file:../deps/phoenix_html",