tests: fix unclosed ssl socket warnings

Fix all but one that it's still pending

src/popper/runner_kubernetes.py

@@ -45,6 +45,8 @@ def __init__(self, **kw):
         self._vol_claim_created = False
 
     def __exit__(self, exc_type, exc_value, exc_traceback):
+        self._kclient.api_client.rest_client.pool_manager.clear()
+        self._kclient.api_client.close()
         super(KubernetesRunner, self).__exit__(exc_type, exc_value, exc_traceback)
         return True
 
@@ -477,3 +479,7 @@ class DockerRunner(KubernetesRunner, HostDockerRunner):
 
     def __init__(self, **kw):
         super(DockerRunner, self).__init__(**kw)
+
+    def __exit__(self, exc_type, exc_value, exc_traceback):
+        super(DockerRunner, self).__exit__(exc_type, exc_value, exc_traceback)
+        return True

src/test/test_parser.py

@@ -12,15 +12,9 @@ def tearDown(self):
         log.setLevel("NOTSET")
 
     def test_empty_file(self):
-        try:
-            f = open("test.yml", "a")
-            f.close()
-            WorkflowParser.parse(file="test.yml")
-            self.assertTrue(False, "Empty Workflow file does not raise an exception.")
-        except SystemExit:
-            self.assertTrue(True)
-        else:
-            self.assertTrue(False, "Empty Workflow file does not raise a SystemExit.")
+        with open("/tmp/test.yml", "w"):
+            pass
+        self.assertRaises(SystemExit, WorkflowParser.parse, **{"file": "/tmp/test.yml"})
 
     def test_new_workflow(self):
         wf_data = {}

src/test/test_runner_kubernetes.py

@@ -37,6 +37,8 @@ def setUp(self):
         config.list_kube_config_contexts()
 
     def tearDown(self):
+        self._kclient.api_client.rest_client.pool_manager.clear()
+        self._kclient.api_client.close()
         log.setLevel("NOTSET")
 
     def test_vol_claim_create_delete(self):