latestMigrationVersion static method
Sort migrations by their version number in ascending order
and return the latest Migration version or 0 if allMigrations is empty
Implementation
static int latestMigrationVersion(Iterable<Migration> allMigrations) {
  if (allMigrations.isEmpty) {
    return 0;
  }
  final versions = allMigrations.map((m) => m.version).toList()..sort();
  return versions.last;
}