Do not abort wait_for_provision_state of last_errors becomes non-empty

It can happen if one of heartbeats encounteres "node locked" error, which
is normal, because the next heartbeat will succeed.

Change-Id: Iaed9b83e199761eac4e0e2157c16ea1efa564c24
Story: #2002094
Task: #19772

ironicclient/tests/unit/v1/test_node.py

@@ -1578,7 +1578,9 @@ class NodeManagerTest(testtools.TestCase):
     def test_wait_for_provision_state(self, mock_get, mock_sleep):
         mock_get.side_effect = [
             self._fake_node_for_wait('deploying', target='active'),
-            self._fake_node_for_wait('deploying', target='active'),
+            # Sometimes non-fatal errors can be recorded in last_error
+            self._fake_node_for_wait('deploying', target='active',
+                                     error='Node locked'),
             self._fake_node_for_wait('active')
         ]
 

ironicclient/v1/node.py

@@ -653,7 +653,7 @@ class NodeManager(base.CreateManager):
                 return
 
             # Note that if expected_state == 'error' we still succeed
-            if (node.last_error or node.provision_state == 'error' or
+            if (node.provision_state == 'error' or
                     node.provision_state.endswith(' failed')):
                 raise exc.StateTransitionFailed(
                     _('Node %(node)s failed to reach state %(state)s. '

releasenotes/notes/wait-for-prov-last-error-5f49b1c488879775.yaml

@@ -0,0 +1,8 @@
+---
+fixes:
+  - |
+    Waiting for a provision state to be reached (via CLI ``--wait`` argument or
+    the ``wait_for_provision_state`` function) no longer aborts when the node's
+    ``last_error`` field gets populated. It can cause a normal deployment to
+    abort if a heartbeat from the ramdisk fails because of locking - see
+    `story 2002094 <https://storyboard.openstack.org/#!/story/2002094>`_.