test: fix start-lambda-no-containers test (#8490)

Also move the creation of the local Lambda client to a separate function

Author: valerena

tests/integration/local/start_lambda/start_lambda_api_integ_base.py

@@ -8,6 +8,9 @@
 import logging
 from pathlib import Path
 
+import boto3
+from botocore import UNSIGNED
+from botocore.config import Config
 from docker.errors import APIError
 from psutil import NoSuchProcess
 
@@ -225,6 +228,17 @@ def tearDownClass(cls):
         except Exception as ex:
             LOG.error("Failed to clean up SAM CLI containers", exc_info=ex)
 
+    def get_local_lambda_client(self):
+        url = "http://127.0.0.1:{}".format(self.port)
+        return boto3.client(
+            "lambda",
+            endpoint_url=url,
+            region_name="us-east-1",
+            use_ssl=False,
+            verify=False,
+            config=Config(signature_version=UNSIGNED, read_timeout=120, retries={"max_attempts": 0}),
+        )
+
 
 class WatchWarmContainersIntegBaseClass(StartLambdaIntegBaseClass):
     temp_path: Optional[str] = None