v7.0.0

• BUGFIX: Remove internal-only fields from serialized metrics data (#550)
• FEATURE: New subcommand: dump to dump the metrics data as JSON (#550)
• BUGFIX: Kotlin: Generate enums with the right generic bound for ping reason codes (#551).
• BREAKING CHANGE: Fully remove support for the old events API (#549)
  Adds a new lint OLD_EVENT_API to warn about missing type attributes on event extra keys.
  Note that the Glean SDK already dropped support for the old events API.