Bulk import cleanup (ansible-collections#360)

* Split imports and reorder
* Import camel_dict_to_snake_dict and snake_dict_to_camel_dict direct from ansible.module_utils.common.dict_transformations
* Remove unused imports
* Route53 Info was migrated to Boto3 drop the HAS_BOTO check and import
* changelog

This commit was initially merged in https://github.com/ansible-collections/community.aws
See: ansible-collections/community.aws@130cf3c

plugins/modules/lambda_event.py

@@ -115,17 +115,16 @@
 '''
 
 import re
-import sys
 
 try:
-    import boto3
     from botocore.exceptions import ClientError, ParamValidationError, MissingParametersError
 except ImportError:
     pass  # Handled by AnsibleAWSModule
 
+from ansible.module_utils.common.dict_transformations import camel_dict_to_snake_dict
+
 from ansible_collections.amazon.aws.plugins.module_utils.core import AnsibleAWSModule
 from ansible_collections.amazon.aws.plugins.module_utils.ec2 import boto3_conn
-from ansible_collections.amazon.aws.plugins.module_utils.ec2 import camel_dict_to_snake_dict
 from ansible_collections.amazon.aws.plugins.module_utils.ec2 import get_aws_connection_info