[docs] Correct version on themed example

[bharatkashyap]

• https://deploy-preview-4405--mui-toolpad-docs.netlify.app/toolpad/core/introduction/examples/

[prakhargupta1]

https://github.com/mui/toolpad/blob/master/examples/core/auth-nextjs-passkey/package.json and https://github.com/mui/toolpad/blob/master/examples/core/auth-vite/package.json have "@toolpad/core": "workspace:*" configuration, but other have 'latest'. IDK if this needs to be fixed.

[bharatkashyap]

https://github.com/mui/toolpad/blob/master/examples/core/auth-nextjs-passkey/package.json and https://github.com/mui/toolpad/blob/master/examples/core/auth-vite/package.json have "@toolpad/core": "workspace:*" configuration, but other have 'latest'. IDK if this needs to be fixed.

Good catch, all of these should be latest. I'll correct this here