chore: minimum required nodejs version is 8.9.0 (webpack-contrib#948)

BREAKING CHANGE: minimum required nodejs version is 8.9.0

Author: evilebottnawi

.github/CONTRIBUTING.md

@@ -131,6 +131,22 @@ Migration: see webpack/webpack#5225
 
 ```
 
+## Testing Your Pull Request
+
+You may have the need to test your changes in a real-world project or dependent
+module. Thankfully, Github provides a means to do this. Add a dependency to the
+`package.json` for such a project as follows:
+
+```json
+{
+  "devDependencies": {
+    "css-loader": "webpack-contrib/css-loader#{id}/head"
+  }
+}
+```
+
+Where `{id}` is the # ID of your Pull Request.
+
 ## Thanks
 
 For your interest, time, understanding, and for following this simple guide.

azure-pipelines.yml

@@ -36,7 +36,7 @@ jobs:
     pool:
       vmImage: ubuntu-16.04
     strategy:
-      maxParallel: 5
+      maxParallel: 4
       matrix:
         node-12:
           node_version: ^12.0.0
@@ -47,9 +47,6 @@ jobs:
         node-8:
           node_version: ^8.9.0
           webpack_version: latest
-        node-6:
-          node_version: ^6.9.0
-          webpack_version: latest
         node-8-canary:
           node_version: ^8.9.0
           webpack_version: next
@@ -91,7 +88,7 @@ jobs:
     pool:
       vmImage: macOS-10.14
     strategy:
-      maxParallel: 5
+      maxParallel: 4
       matrix:
         node-12:
           node_version: ^12.0.0
@@ -102,9 +99,6 @@ jobs:
         node-8:
           node_version: ^8.9.0
           webpack_version: latest
-        node-6:
-          node_version: ^6.9.0
-          webpack_version: latest
         node-8-canary:
           node_version: ^8.9.0
           webpack_version: next
@@ -146,7 +140,7 @@ jobs:
     pool:
       vmImage: windows-2019
     strategy:
-      maxParallel: 5
+      maxParallel: 4
       matrix:
         node-12:
           node_version: ^12.0.0
@@ -157,9 +151,6 @@ jobs:
         node-8:
           node_version: ^8.9.0
           webpack_version: latest
-        node-6:
-          node_version: ^6.9.0
-          webpack_version: latest
         node-8-canary:
           node_version: ^8.9.0
           webpack_version: next

babel.config.js

@@ -10,7 +10,7 @@ module.exports = (api) => {
         '@babel/preset-env',
         {
           targets: {
-            node: '6.9.0',
+            node: '8.9.0',
           },
         },
       ],