Update Docusaurus metadata (reduxjs#3881)

* Update Docusaurus to alpha.64

* Fix validation issues and swap Twitter card config

* Fix broken Immutable FAQ link

Former-commit-id: ab0b746

Author: markerikson

docs/recipes/UsingImmutableJS.md.REMOVED.git-id

@@ -1 +1 @@
-3fb34cbeecfae68f4ea504c6fed7c618002e9a9e
+0bc33b24d5ef987d98dc222ac56457676b239a52

website/docusaurus.config.js

@@ -7,19 +7,21 @@ module.exports = {
   organizationName: 'reduxjs',
   projectName: 'redux',
   themeConfig: {
-    image: 'https://redux.js.org/img/redux-logo-landscape.png',
-    disableDarkMode: false,
+    image: 'img/redux-logo-landscape.png',
+    metadatas: [{ name: 'twitter:card', content: 'summary' }],
     prism: {
       theme: require('./src/js/monokaiTheme.js')
     },
+    colorMode: {
+      disableSwitch: false
+    },
     navbar: {
       title: 'Redux',
-      image: 'img/redux-logo-landscape.png',
       logo: {
         alt: 'Redux Logo',
         src: 'img/redux.svg'
       },
-      links: [
+      items: [
         {
           label: 'Getting Started',
           to: 'introduction/getting-started',

website/package-lock.json.REMOVED.git-id

@@ -6,8 +6,8 @@
     "deploy": "docusaurus deploy"
   },
   "dependencies": {
-    "@docusaurus/core": "2.0.0-alpha.54",
-    "@docusaurus/preset-classic": "2.0.0-alpha.54",
+    "@docusaurus/core": "2.0.0-alpha.64",
+    "@docusaurus/preset-classic": "2.0.0-alpha.64",
     "classnames": "2.2.6",
     "react": "16.13.0",
     "react-dom": "16.13.0"