Weaver live check test util

[lmolkova]

Description

Adds WeaverLiveCheck helper that allows to validate instrumentation output against otel semconv.

Examples:

1. you can call report = check.end() and it won't raise. You can explore report (which contains a list of violations and also full weaver report as dict from json) - party on

        with WeaverLiveCheck() as weaver:
            # ... configure provider, emit telemetry ...
            provider.force_flush()
            report = weaver.end()

        seen_metrics = report["statistics"]["seen_registry_metrics"]
        self.assertEqual(seen_metrics.get("test.metric"), 1)

2. you can call report = check.end_and_check() and it'd raise LiveCheckError (extends AssertionError) if any violations are found. You still get full report as a property on the error if you want to assert on more

        with WeaverLiveCheck() as weaver:
            # ... configure provider, emit telemetry ...
            provider.force_flush()

            with self.assertRaises(LiveCheckError) as cm:
                weaver.end_and_check()

        seen_metrics = cm.exception.report["statistics"]["seen_registry_metrics"]
        self.assertEqual(seen_metrics.get("test.metric"), 1)

Checklist:

• Followed the style guidelines of this project
• Changelogs have been updated
• Unit tests have been added
• Documentation has been updated

[xrmx]

Love this, thanks a lot!

[MikeGoldsmith]

🚀