Add GH workflow to check if datasources are working

[onprem]

Description

The step to check if datasources are working was removed during the CLI removal PR. This PR adds it back in the form of another GH workflow. We cannot use the e2e test job as before as ct install immediately cleans up after itself as well.

Fixes #517

Type of change

What type of changes does your code introduce to tobs? Put an x in the box that apply.

• [ ] CHANGE (fix or feature that would cause existing functionality to not work as expected)
• [ ] FEATURE (non-breaking change which adds functionality)
• [ ] BUGFIX (non-breaking change which fixes an issue)
• [ ] ENHANCEMENT (non-breaking change which improves existing functionality)
• [x] NONE (if none of the other choices apply. Example, tooling, build system, CI, docs, etc.)

[onprem]

Closing as it has been superseded by #521.