With #15995 merged, we should convert existing promql tests to the new syntax.

See the documentation in https://github.com/prometheus/prometheus/blob/main/promql/promqltest/README.md (look for "deprecated".

And note the sentence "Previously eval expected no info or warn annotation, but now expect no_info and expect no_warn lines must be explicitly provided." For the conversions, we should not add expect no_info and expect no_warn everywhere, but only where the tests are meant to test for that. (Use you best judgement...)

Bonus point for providing a simple script (in a suitable language of your choice) to convert tests automatically.