update deps (#175)

.postcssrc.js

@@ -1,7 +1,7 @@
 module.exports = {
   plugins: {
     autoprefixer: {
-      browsers: ['>1%', 'last 2 versions', 'not ie < 11']
+      overrideBrowserslist: ['>1%', 'last 2 versions', 'not ie < 11']
     }
   }
 };

.sassrc.js

@@ -3,7 +3,7 @@ const path = require('path')
 const CWD = process.cwd()
 
 module.exports = {
-  "includePaths": [
+  includePaths: [
     path.resolve(CWD, 'node_modules'),
     path.resolve(CWD, 'src')
   ]

package.json

@@ -24,18 +24,18 @@
     "deploy": "gh-pages --dist dist"
   },
   "devDependencies": {
-    "@primer/css": "^12.2.3",
-    "autoprefixer": "^9.5.1",
+    "@primer/css": "^12.4.1",
+    "autoprefixer": "^9.6.0",
     "gh-pages": "^2.0.1",
     "github-syntax-dark": "^0.5.0",
     "github-syntax-light": "^0.5.0",
     "parcel-bundler": "^1.12.3",
     "parcel-plugin-clean-dist": "^0.0.6",
-    "posthtml-expressions": "^1.1.0",
+    "posthtml-expressions": "^1.1.1",
     "posthtml-include": "^1.2.0",
     "posthtml-md": "^1.1.0",
-    "sass": "^1.19.0",
-    "tslint": "^5.16.0",
-    "typescript": "^3.4.5"
+    "sass": "^1.21.0",
+    "tslint": "^5.18.0",
+    "typescript": "^3.5.2"
   }
 }