Linting GitHub workflows

[rartych]

What type of PR is this?

• subproject management

What this PR does / why we need it:

The changes follow the instructions in API-linting-Implementation-Guideline.md

Which issue(s) this PR fixes:

Fixes #

Special notes for reviewers:

yamllint errors corrected in sim-swap-notification-subscription.yaml

Changelog input

Linting ruleset configured in Github Actions

Additional documentation

This section can be blank.

[AxelNennker]

/LGTM