[cloud] Remove repeated error handling and region checking, both now in boto3_conn (#32774)

* Remove boto usage from boto3 modules

* Remove region checking

boto3_conn now takes care of region checking and handles NoRegionError
exceptions with a standard message

boto3_conn also takes care of other connection exceptions too.

* Document boto3 as a requirement for ec2_eni_facts

lib/ansible/modules/cloud/amazon/ecs_taskdefinition.py

@@ -27,7 +27,7 @@ description:
     - Registers or deregisters task definitions in the Amazon Web Services (AWS) EC2 Container Service (ECS)
 version_added: "2.0"
 author: Mark Chance(@Java1Guy)
-requirements: [ json, boto, botocore, boto3 ]
+requirements: [ json, botocore, boto3 ]
 options:
     state:
         description:
@@ -114,15 +114,9 @@ taskdefinition:
     type: dict
     returned: always
 '''
-try:
-    import boto
-    import botocore
-    HAS_BOTO = True
-except ImportError:
-    HAS_BOTO = False
 
 try:
-    import boto3
+    import botocore
     HAS_BOTO3 = True
 except ImportError:
     HAS_BOTO3 = False
@@ -138,13 +132,8 @@ class EcsTaskManager:
     def __init__(self, module):
         self.module = module
 
-        try:
-            region, ec2_url, aws_connect_kwargs = get_aws_connection_info(module, boto3=True)
-            if not region:
-                module.fail_json(msg="Region must be specified as a parameter, in EC2_REGION or AWS_REGION environment variables or in boto configuration file")
-            self.ecs = boto3_conn(module, conn_type='client', resource='ecs', region=region, endpoint=ec2_url, **aws_connect_kwargs)
-        except boto.exception.NoAuthHandlerFound as e:
-            module.fail_json(msg="Can't authorize connection - " % str(e))
+        region, ec2_url, aws_connect_kwargs = get_aws_connection_info(module, boto3=True)
+        self.ecs = boto3_conn(module, conn_type='client', resource='ecs', region=region, endpoint=ec2_url, **aws_connect_kwargs)
 
     def describe_task(self, task_name):
         try:
@@ -233,9 +222,6 @@ def main():
 
     module = AnsibleModule(argument_spec=argument_spec, supports_check_mode=True)
 
-    if not HAS_BOTO:
-        module.fail_json(msg='boto is required.')
-
     if not HAS_BOTO3:
         module.fail_json(msg='boto3 is required.')