Bug fixes and cleanup for ansible-test. (#45991)

* Remove unused imports.
* Clean up ConfigParser usage in ansible-test.
* Fix bare except statements in ansible-test.
* Miscellaneous cleanup from PyCharm inspections.
* Enable pylint no-self-use for ansible-test.
* Remove obsolete pylint ignores for Python 3.7.
* Fix shellcheck issuers under newer shellcheck.
* Use newer path for ansible-test.
* Fix issues in code-smell tests.

test/runner/lib/cloud/tower.py

@@ -4,20 +4,13 @@ from __future__ import absolute_import, print_function
 import os
 import time
 
-try:
-    # noinspection PyPep8Naming
-    import ConfigParser as configparser
-except ImportError:
-    # noinspection PyUnresolvedReferences
-    import configparser
-
 from lib.util import (
     display,
     ApplicationError,
     is_shippable,
     run_command,
-    generate_password,
     SubprocessError,
+    ConfigParser,
 )
 
 from lib.cloud import (
@@ -27,15 +20,6 @@ from lib.cloud import (
 
 from lib.core_ci import (
     AnsibleCoreCI,
-    InstanceConnection,
-)
-
-from lib.manage_ci import (
-    ManagePosixCI,
-)
-
-from lib.http import (
-    HttpClient,
 )
 
 
@@ -219,7 +203,7 @@ class TowerConfig(object):
         :type path: str
         :rtype: TowerConfig
         """
-        parser = configparser.RawConfigParser()
+        parser = ConfigParser()
         parser.read(path)
 
         keys = (