I've seen the same error just once (out of 5 or 6 tries), and,
coincidentally, had the same error notified "Failed to store notification:
{"type":"RESOURCE_ADDED" etc." with "MethodNotAllowed"
at the very same
moment, that is, just when the testRemoveXaDatasource test runs.
That's maybe a trail to investigate, maybe it betrays some server-side
malfunction. I don't know if it's possible to see server-side logs during
agent itests, but it would probably help. I don't know why this error
happens.
When I run tests successfully, I also see from times to times this error,
but it's distributed randomly in tests, and fortunately or not (rather
not), tests pass.