Fix more file opening ResourceWarnings

I've managed to get better at grepping for this and this finds some of
the stragglers. They are all file opens without closes fixed by using a
with open() context manager.

Change-Id: I7b8c8516a86558e2027cb0f01aefe2dd1849069c

tests/make_playbooks.py

@@ -40,7 +40,8 @@ def handle_repo(path):
             config_path = os.path.join(path, fn)
             break
     try:
-        config = yaml.safe_load(open(config_path))
+        with open(config_path) as f:
+            config = yaml.safe_load(f)
     except Exception:
         print("  Has yaml errors")
         return

tests/unit/test_git_driver.py

@@ -62,7 +62,8 @@ class TestGitDriver(ZuulTestCase):
 
         # Update zuul.yaml to force a tenant reconfiguration
         path = os.path.join(self.upstream_root, 'common-config', 'zuul.yaml')
-        config = yaml.safe_load(open(path, 'r').read())
+        with open(path, 'r') as f:
+            config = yaml.safe_load(f)
         change = {
             'name': 'org/project',
             'check': {

tests/unit/test_scheduler.py

@@ -6199,7 +6199,8 @@ For CI problems and help debugging, contact ci@example.org"""
 
         build = self.getBuildByName('check-job')
         inv_path = os.path.join(build.jobdir.root, 'ansible', 'inventory.yaml')
-        inventory = yaml.safe_load(open(inv_path, 'r'))
+        with open(inv_path, 'r') as f:
+            inventory = yaml.safe_load(f)
         label = inventory['all']['hosts']['controller']['nodepool']['label']
         self.assertEqual('slow-label', label)
 

zuul/ansible/logconfig.py

@@ -140,7 +140,8 @@ def _read_config_file(filename: str):
         raise ValueError("Unable to read logging config file at %s" % filename)
 
     if os.path.splitext(filename)[1] in ('.yml', '.yaml', '.json'):
-        return yaml.safe_load(open(filename, 'r'))
+        with open(filename, 'r') as f:
+            return yaml.safe_load(f)
     return filename