* Add unit tests for `FlowFork` activity and enhance test utilities
- Introduce `FlowForkTests` to validate activity behavior with various branch configurations.
- Extend `ActivityExecutionContextExtensions` with methods to retrieve and check outcomes.
- Modify `ActivityTestFixture` to ensure activities transition to `Running` status before execution.
* Apply suggestion from @Copilot
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
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Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
