Update pytest from 3.6.3 to 3.6.4 (#3841)
Update pytest from 3.6.3 to 3.6.4 (#3841)


KWierso/treeherder,edmorley/treeherder,KWierso/treeherder,KWierso/treeherder,edmorley/treeherder,edmorley/treeherder,KWierso/treeherder,edmorley/treeherder