Missing cloudwatch:DescribeAlarmHistory in serverless function Policy List

[zmaleki]

Description:
We have a lambda that requires cloudwatch:DescribeAlarmHistory and we want to use sam template for our lambda. However, DescribeAlarmHistory is not one of the available policies.

Steps to reproduce the issue:
Pull request #1264

[chrisoverzero]

Is there a reason that your application requires such a specific SAM Policy Template instead of using an IAM Policy object? Arbitrary policies can be assigned to Functions, as you can see in some of the example applications.