docs: update deprecated option in tools.md (#4467)

Co-authored-by: Lukas Taegert-Atkinson <lukastaegert@users.noreply.github.com>

docs/07-tools.md

@@ -100,9 +100,7 @@ export default {
   plugins: [
     resolve({
       // pass custom options to the resolve plugin
-      customResolveOptions: {
-        moduleDirectory: 'node_modules'
-      }
+      moduleDirectories: ['node_modules']
     })
   ],
   // indicate which modules should be treated as external