Use buf lint on the CI

[hug-dev]

With the added buf.yaml file, we should look into fixing the buf lint errors and adding it to the CI. See here for details. See also this conversation on Slack.

Relevent issues that might have to be adressed in the same time:

• Add namespacing for Core and PSA structures parsec-interface-rs#35
• Refactor ResponseStatus parsec-interface-rs#56