Add GitHub action for testing SDK:latest -> Databroker:main / latest

[Chrylo]

Is your feature request related to a problem? Please describe.
There is currently no warning system if the currently released SDK (latest) will be outdated / incompatible with the upcoming KUKSA Databroker release.

See #63

Describe the solution you'd like

• SDK:latest will be tested against databroker:main + latest on a daily basis via GitHub actions.
• Add GitHub Badge for successful / failing build (Add text like "main vs main" so it is clear what the badge validates)
• Add chapter on how to act on failed build to the CONTRIBUTING.md file.
  In this case:

1. If SDK:latest failed against databroker:main then it should be considered as a warning -> A ticket for adapting the SDK may have to be created.
2. If SDK:latest failed against databroker:latest then it should be considered as a bigger potential problem -> A hotfix or new release has to be done most likely.

Additional Context

Instead of doing daily builds it is more optimal to react on a trigger from the Databroker repository e.g. the master/main has a new commit: Research if this is possible/feasible

latest = latest release

https://docs.github.com/en/actions/monitoring-and-troubleshooting-workflows/adding-a-workflow-status-badge