Simplify with-absolute-imports example (#5812)

* Delete .babelrc

* Update package.json

* Create next.config.js

* Update next.config.js

examples/with-absolute-imports/.babelrc

-{
-  "presets": ["next/babel"],
-  "plugins": [
-    [
-      "module-resolver",
-      {
-        "root": ["./"],
-        "alias": {
-          "components": "./components"
-        }
-      }
-    ]
-  ]
-}

examples/with-absolute-imports/next.config.js

+const path = require('path')
+
+module.exports = {
+  webpack (config, options) {
+    config.resolve.alias['components'] = path.join(__dirname, 'components')
+    return config
+  }
+}

examples/with-absolute-imports/package.json

@@ -8,8 +8,5 @@
     "next": "latest",
     "react": "^16.1.1",
     "react-dom": "^16.1.1"
-  },
-  "devDependencies": {
-    "babel-plugin-module-resolver": "^3.1.1"
   }
 }