fix: use correct defnition field name for CFN resources

[mndeveci]

Which issue(s) does this change fix?

N/A

Why is this change necessary?

In get_definition_path it is been hardcoded to use DefinitionUri field to find definition files for APIGW and SFN resources. All AWS::Serverless::* resources uses that field, but their CFN equivalents have different fields.

How does it address the issue?

This PR addresses that by using the property definition that we have in RESOURCES_WITH_LOCAL_PATHS.

What side effects does this change have?

N/A

Mandatory Checklist

PRs will only be reviewed after checklist is complete

• Add input/output type hints to new functions/methods
• Write design document if needed (Do I need to write a design document?)
• Write/update unit tests
• Write/update integration tests
• Write/update functional tests if needed
• make pr passes
• make update-reproducible-reqs if dependencies were changed
• Write documentation

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.