Recorder Exception When Beginning Segment

[mjtieman]

AWSXRayRecorder is throwing a TypeError when creating a new segment. The exception is being thrown because the recorder is calling should_trace on the sampler, which starting in 2.0 requires sample_req.

Stack trace

should_trace() takes exactly 2 arguments (1 given): TypeError
Traceback (most recent call last):
File "/var/task/src/setup_database.py", line 55, in handler
xray_recorder.begin_segment('setup_database.handler')
File "/var/task/aws_xray_sdk/core/recorder.py", line 208, in begin_segment
decision = self._sampler.should_trace()
TypeError: should_trace() takes exactly 2 arguments (1 given)

[haotianw465]

Thank you for your contribution. I have merged your PR and will prepare a release soon.

[mjtieman]

Changes merged