Description

Users #3875 (comment) issues with the schema because they don't update it.
Biome has a dedicated command to update the schema and migrate to a new version: biome migrate.
We recommend users to run it on every update of Biome.

When a user runs Biome (biome format, biome check, biome lint), we should emit a warning if the $schema of the Biome configuration doesn't match the current version of Biome.
If the version of the schema is outdated we could advise running biome migrate --write, otherwise if it is a newer version, we could advise setting the $schema to the current version.

Note that we should not emit any warning if we are not able to retrieve the version of $schema. This is the case when users use a local schema such as /node_modules/@biomejs/biome/configuration_schema.json. Basically we should only parse URLs like https://biomejs.dev/schemas/<version>/schema.json.