Add isort and flake8 to CI (#869)

* Run isort.

* Clean up unused assignments.

* Add flake8 linting step.

plugins/modules/ecs_certificate.py

@@ -6,6 +6,8 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
 
 from __future__ import absolute_import, division, print_function
+
+
 __metaclass__ = type
 
 
@@ -550,13 +552,6 @@ cert_details:
   type: dict
 """
 
-from ansible_collections.community.crypto.plugins.module_utils.ecs.api import (
-    ecs_client_argument_spec,
-    ECSClient,
-    RestOperationException,
-    SessionConfigurationException,
-)
-
 import datetime
 import os
 import re
@@ -564,17 +559,21 @@ import time
 import traceback
 
 from ansible.module_utils.basic import AnsibleModule, missing_required_lib
-from ansible.module_utils.common.text.converters import to_native, to_bytes
-
-from ansible_collections.community.crypto.plugins.module_utils.version import LooseVersion
-
-from ansible_collections.community.crypto.plugins.module_utils.io import (
-    write_file,
-)
-
+from ansible.module_utils.common.text.converters import to_bytes, to_native
 from ansible_collections.community.crypto.plugins.module_utils.crypto.support import (
     load_certificate,
 )
+from ansible_collections.community.crypto.plugins.module_utils.ecs.api import (
+    ECSClient,
+    RestOperationException,
+    SessionConfigurationException,
+    ecs_client_argument_spec,
+)
+from ansible_collections.community.crypto.plugins.module_utils.io import write_file
+from ansible_collections.community.crypto.plugins.module_utils.version import (
+    LooseVersion,
+)
+
 
 CRYPTOGRAPHY_IMP_ERR = None
 try:
@@ -648,7 +647,7 @@ class EcsCertificate(object):
         if self.path and os.path.exists(self.path):
             try:
                 self.cert = load_certificate(self.path, backend='cryptography')
-            except Exception as dummy:
+            except Exception:
                 self.cert = None
         # Instantiate the ECS client and then try a no-op connection to verify credentials are valid
         try:
@@ -733,7 +732,7 @@ class EcsCertificate(object):
             cert_results = self.ecs_client.GetCertificates(serialNumber=serial_number).get('certificates', {})
             if len(cert_results) == 1:
                 self.tracking_id = cert_results[0].get('trackingId')
-        except RestOperationException as dummy:
+        except RestOperationException:
             # If we fail to find a cert by serial number, that's fine, we just do not set self.tracking_id
             return