Upgrade PostCSS to 7.0.2

Aaron Ballard · jonathantneal · commit b2a385a23cd3 · 2018-08-15T20:02:38.000-04:00
diff --git a/package.json b/package.json
@@ -26,7 +26,7 @@
   },
   "dependencies": {
     "@csstools/convert-colors": "^1.4.0",
-    "postcss": "^6.0.23",
+    "postcss": "^7.0.2",
     "postcss-values-parser": "^1.5.0"
   },
   "devDependencies": {
