Create test action

[larf311]

We need to create a github action that runs the tests that conforms to the same interface as all the others:

E.g. it should look almost identical to this:
https://github.com/RelationalAI/rai-sdk-csharp/blob/main/.github/actions/test/action.yml

The tests also need to support custom headers.

[billscheidel-rai]

Note: This issue has been migrated to https://relationalai.atlassian.net/browse/RAI-7959.

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