message: Add migration to mark doc_targets as non-nullable
diff: @@ -310,6 +310,21 @@ pub fn migrate(version: Option<Version>, conn: &Connection) -> CratesfyiResult<(
  // downgrade query
  "DROP TABLE crate_priorities;",
  ),
  + migration!(
  + context,
  + // version
  + 12,
  + // description
  + "Mark doc_targets non-nullable (it has a default of empty array anyway)",
  + // upgrade query
  + "
  + ALTER TABLE releases ALTER COLUMN doc_targets SET NOT NULL;
  + ",
  + // downgrade query
  + "
  + ALTER TABLE releases ALTER COLUMN doc_targets DROP NOT NULL;
  + "
  + ),
  ];
  for migration in migrations {
  