fetch experiment run results from dc

[FHardow]

Related Issue(s): ... https://github.com/deepset-ai/haystack/issues/2924

Proposed changes: Adds the functionality in the SDK to fetch the results from an experiment run in DC.

Pre-flight checklist

• [x] I have read the contributors guidelines
• [x] I have enabled actions on my fork
• [x] If this is a code change, I added tests or updated existing ones
• [x] If this is a code change, I updated the docstrings

[FHardow]

@FHardow can we add a test for get_run_results() too please?

Sure. I couldn't find tests for the other functions in that class and skipped them.

[tstadel]

@FHardow can we add a test for get_run_results() too please?

Sure. I couldn't find tests for the other functions in that class and skipped them.

The others are merely proxies to client functions. This one however feeds the EvaluationResult object. I just want to make sure, this works.

[FHardow]

@agnieszka-m thanks for the amazing review!