Start worker thread number at 1

This number is only for human consumption and startng at 1 seems more
user friendly to me.

Author: NicolasLM

spinach/worker.py

@@ -44,7 +44,7 @@ def __init__(self, num_workers: int, namespace: str):
         self._must_stop = threading.Event()
         self.poison_pill = object()
 
-        for i in range(num_workers):
+        for i in range(1, num_workers + 1):
             thread = threading.Thread(
                 target=self._worker_func,
                 name='{}-worker-{}'.format(self._namespace, i)

tests/test_worker.py

@@ -136,10 +136,10 @@ def test_worker_signals(job):
     mock_job_started_receiver.assert_called_once_with(ns, job=ANY)
     mock_job_finished_receiver.assert_called_once_with(ns, job=ANY)
     mock_worker_started_receiver.assert_called_once_with(
-        ns, worker_name='tests-worker-0'
+        ns, worker_name='tests-worker-1'
     )
     mock_worker_terminated_receiver.assert_called_once_with(
-        ns, worker_name='tests-worker-0'
+        ns, worker_name='tests-worker-1'
     )