docs: @DELETE
      @Path("/clusters/{clusterid: ([A-Z,a-z,0-9,_,\\-]+)}")
      public Response migrateCluster(@PathParam("clusterid") final String clusterId) {
  
          // as this is a long running task, this has to be asynchronous
          migrationService.startClusterMigration(clusterId);
  
          return Response.status(202 /* Accepted */).build();
      }