chore: Test Docusaurus webpack 5 support (#974)

* webpack 5

* test commit

* test

* update

* test

* upgrade docu

* upgrade docu

Author: slorber

netlify.toml

@@ -5,3 +5,10 @@
 
 [build.environment]
   NODE_VERSION = "12.13"
+
+[[plugins]]
+  package = "netlify-plugin-cache"
+  [plugins.inputs]
+    paths = [
+      "node_modules/.cache",
+    ]

package.json

@@ -12,15 +12,16 @@
     "fetch-sponsors": "node scripts/fetch-sponsors.js"
   },
   "dependencies": {
-    "@docusaurus/core": "^2.0.0-alpha.72",
-    "@docusaurus/plugin-google-analytics": "^2.0.0-alpha.66",
-    "@docusaurus/preset-classic": "^2.0.0-alpha.72",
+    "@docusaurus/core": "2.0.0-alpha.75",
+    "@docusaurus/plugin-google-analytics": "2.0.0-alpha.75",
+    "@docusaurus/preset-classic": "2.0.0-alpha.75",
     "@octokit/graphql": "^4.5.7",
     "@react-navigation/core": "^5.14.3",
     "classnames": "^2.2.6",
     "docsearch.js": "^2.6.3",
     "escape-html": "^1.0.3",
     "mkdirp": "^1.0.4",
+    "netlify-plugin-cache": "^1.0.3",
     "prism-react-renderer": "^1.1.1",
     "react": "^17.0.1",
     "react-dom": "^17.0.1",