Dev middleware TimeMonitoring does not work on Macs

[joemull]

Problem

The TimeMonitoring middleware does not work on Darwin / Mac OSX due to an unavailable attribute resource.RUSAGE_THREAD.

janeway/src/utils/middleware.py

Lines 76 to 79 in 30fb420

	@staticmethod
	def _get_usage():
	utime, stime, *_ = resource.getrusage(resource.RUSAGE_THREAD)
	return (time.time(), utime, stime)

Proposed solution

Add a try / except to catch the attribute error, and try to fetch the appropriate Darwin resource. If that does not work, exit the middleware gracefully but allow Janeway to run.