message: add missing usage.json to v5 sdk tag
diff: @@ -51,6 +51,7 @@ input-file:
  - Microsoft.Sql/stable/2014-04-01/serviceObjectives.json
  - Microsoft.Sql/stable/2014-04-01/sql.core_legacy.json
  - Microsoft.Sql/stable/2014-04-01/usages_legacy.json
  +- Microsoft.Sql/preview/2018-06-01-preview/usages.json
  - ./Microsoft.Sql/preview/2020-11-01-preview/BackupShortTermRetentionPolicies.json
  - ./Microsoft.Sql/preview/2020-11-01-preview/BlobAuditing.json
  - ./Microsoft.Sql/preview/2020-11-01-preview/DatabaseAdvisors.json
  