Is your feature request related to a problem?
Looking at the new syntax of updatecli manifest for version 0.17.0 and above like in this PR, we can see the block scms is repeated word for word in every manifest.

Describe the solution you'd like
I'd like the ability to define it globally so we don't have to repeat it on every manifest needing a pull request.

Describe alternatives you've considered
N/A

Additional context
N/A