tests: fix duplicate and failing test There were two "testconflictingrequestid" methods. Naturally this isn't an error in Python. And by our luck, the test was failing. So we rename the test and fix it to pass. As part of this, _sendsingleframe() now takes a frame, not a string describing the frame. This is better because action at a distance can be confusing. Differential Revision: https://phab.mercurial-scm.org/D2950