Makefile: added SSM and AMI validation targets

[mjsterckx]

Description of changes:

• Added cargo make targets for the pubsys validate-ami and pubsys validate-ssm commands created in pubsys: added ami validation #3020 and pubsys: added SSM parameter validation #2969 respectively.
• Added SSM output file arguments to the cargo make ssm and cargo make promote-ssm targets, so the SSM parameters will be written to a file in the same directory as amis.json, with the suffix ssm-params.json.

Testing done:

Ran cargo make, cargo make ami, cargo make ssm, cargo make promote-ssm followed by cargo make validate-ami:

+-----------+---------+-----------+---------+-------------+
| String    | correct | incorrect | missing | unreachable |
+-----------+---------+-----------+---------+-------------+
| us-west-2 | 1       | 0         | 0       | 0           |
+-----------+---------+-----------+---------+-------------+

and cargo make validate-ssm:

+-----------+---------+-----------+---------+------------+-------------+
| String    | correct | incorrect | missing | unexpected | unreachable |
+-----------+---------+-----------+---------+------------+-------------+
| us-west-2 | 4       | 0         | 0       | 0          | 0           |
+-----------+---------+-----------+---------+------------+-------------+

Terms of contribution:

By submitting this pull request, I agree that this contribution is dual-licensed under the terms of both the Apache License, version 2.0, and the MIT license.

[jpmcb]

Nit: Extra space between file. It