Reflect that updateAppMetadata and updateUserMetadata methods were removed

[jmac105]

Changes

V4 migration guide updated to reflect that updateAppMetadata and updateUserMetadata methods were removed, currently the documentation is unclear/incorrect because it suggests there are now ManagementClient.users.updateUserMetadata & ManagementClient.users.updateAppMetadata methods.

References

N/A

Testing

N/A

Checklist

• [X] I have read the Auth0 general contribution guidelines
• [X] I have read the Auth0 Code of Conduct
• [X] All existing and new tests complete without errors