Work around for ansible-collections#1083 (ansible-collections#1086)

Work around for ansible-collections#1083

SUMMARY
The collection currently doesn't run on Ansible 2.9 (which we say we test against).
fixes: ansible-collections#1083
ISSUE TYPE

Bugfix Pull Request

COMPONENT NAME
plugins/module_utils/cloud.py
ADDITIONAL INFORMATION

Reviewed-by: Alina Buzachis <None>

changelogs/fragments/1083-__spec__-is-None.yml

@@ -0,0 +1,2 @@
+bugfixes:
+- 'module_utils/cloud - Fix ``ValueError: ansible_collections.amazon.aws.plugins.module_utils.core.__spec__ is None`` error on Ansible 2.9 (https://github.com/ansible-collections/amazon.aws/issues/1083).'

plugins/module_utils/cloud.py

@@ -32,7 +32,12 @@
 import time
 import functools
 import random
-import ansible.module_utils.common.warnings as ansible_warnings
+
+try:
+    import ansible.module_utils.common.warnings as ansible_warnings
+    ANCIENT_ANSIBLE = False
+except ImportError:
+    ANCIENT_ANSIBLE = True
 
 
 class BackoffIterator:
@@ -200,9 +205,10 @@ def backoff(cls, tries=10, delay=3, backoff=1.1, catch_extra_error_codes=None):
         """
         # This won't emit a warning (we don't have the context available to us), but will trigger
         # sanity failures as we prepare for 6.0.0
-        ansible_warnings.deprecate(
-            'CloudRetry.backoff has been deprecated, please use CloudRetry.exponential_backoff instead',
-            version='6.0.0', collection_name='amazon.aws')
+        if not ANCIENT_ANSIBLE:
+            ansible_warnings.deprecate(
+                'CloudRetry.backoff has been deprecated, please use CloudRetry.exponential_backoff instead',
+                version='6.0.0', collection_name='amazon.aws')
 
         return cls.exponential_backoff(
             retries=tries,