code changes to validate JSON input array

[hrai-nr]

This PR will validate all the JSON array's received as input parameter in the cloud formation stack.
Following is list of validation being done:

1. The input should be a valid JSON array.
2. Each element of array also should be a valid JSON object.
3. Each element should only have required keys, example : AttributeName and AttributeValue in case of CommonAttribute Param.
4. The value of keys should not be empty, example : The value of keys AttributeName and AttributeValue in case of CommonAttribute Param should not be empty. However in case of LogGroupConfig only one key LogGroupName is mandatory.

Testing done:
Passed these values from stack to test all he valid scenarios:

[{"LogGroupName":"xyz-hrai-fifteen", "FilterPattern":"ERROR"}]
[{"LogGroupName":"xyz-hrai-fifteen", "":"ERROR"}]

[{"AttributeName": "name", "AttributeValue": "hrai"}, {"": "surName", "AttributeValue": "hrai-rai"}]
[{"AttributeName": "name", "AttributeValue": "hrai"}, {"AttributeName": "surName", "AttributeValue": "hrai-rai"}