build: Update to Yarn v4. (#116)

Author: milesj

.yarn/plugins/@yarnpkg/plugin-interactive-tools.cjs

@@ -1,11 +1,9 @@
+compressionLevel: mixed
+
 enableGlobalCache: true
 
 enableTelemetry: false
 
 nodeLinker: node-modules
 
-plugins:
-  - path: .yarn/plugins/@yarnpkg/plugin-interactive-tools.cjs
-    spec: '@yarnpkg/plugin-interactive-tools'
-
-yarnPath: .yarn/releases/yarn-3.6.3.cjs
+yarnPath: .yarn/releases/yarn-4.0.1.cjs

.yarn/releases/yarn-3.6.3.cjs

@@ -30,5 +30,5 @@
     "packages/*",
     "website"
   ],
-  "packageManager": "yarn@3.6.3"
+  "packageManager": "yarn@4.0.1"
 }