Fix for timeout warning parameter for GCP integration & UTC time zone for AWS integration (#799)

Co-authored-by: Shantanu  Dhiman <shantanu.dhiman@calsoftinc.com>

Changes:

    Converted local time format to UTC time format for AWS Lambda integration, and verified it on cloudwatch logs.
    Added code for timeout_warning parameter in class GcpIntegration.

Fix #796

Author: shantanu73

sentry_sdk/integrations/gcp.py

@@ -91,6 +91,10 @@ def sentry_func(*args, **kwargs):
 class GcpIntegration(Integration):
     identifier = "gcp"
 
+    def __init__(self, timeout_warning=False):
+        # type: (bool) -> None
+        self.timeout_warning = timeout_warning
+
     @staticmethod
     def setup_once():
         # type: () -> None