Update PostCSS to 7.0.31

Author: C-Lodder

package-lock.json

@@ -27,7 +27,7 @@
   "dependencies": {
     "diff": "^4.0.2",
     "maxmin": "^2.1.0",
-    "postcss": "^7.0.30"
+    "postcss": "^7.0.31"
   },
   "devDependencies": {
     "@lodder/time-grunt": "^4.0.0",
@@ -37,7 +37,7 @@
     "grunt-contrib-jshint": "^2.1.0",
     "grunt-contrib-nodeunit": "^2.1.0",
     "load-grunt-tasks": "^5.1.0",
-    "postcss-scss": "^2.0.0"
+    "postcss-scss": "^2.1.1"
   },
   "peerDependencies": {
     "grunt": ">=1.0.4"