Update unit tests for traceflags 02,03

[tammy-baylis-swi]

Updates unit test coverage as evidence that traceflags 02, 03 are valid for existing APM Python custom sampling and propagation logic.

See ticket for more background information.

[Copilot]

Pull request overview

This PR updates unit tests to explicitly demonstrate that trace flags 0x02 and 0x03 are treated as valid inputs by the existing SolarWinds APM W3C formatting, propagation injection, and custom sampling override behavior.

Changes:

• Expanded W3CTransformer.trace_flags_from_int unit test to cover additional flag values including 0x02 and 0x03.
• Updated propagator test helpers and added injection tests to verify -02 / -03 are preserved in newly created tracestate.
• Added sampler tests to verify sw tracestate decisions -02/-03 override contradictory W3C trace_flags sampled/default state.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
tests/unit/test_w3c_transformer.py	Parametrizes trace-flags formatting assertions to cover 00–03 (and a non-trivial hex value).
tests/unit/test_propagator.py	Allows mocking non-0x01 trace flags and adds injection tests ensuring -02/-03 are preserved in generated tracestate.
tests/unit/test_oboe/test_oboe_sampler.py	Adds sampling tests proving sw tracestate -02/-03 overrides opposing W3C sampled/default flags.

[cheempz]

LGTM