Switch to use test_utils.call_until_true

test.call_until_true has been deprecated since Newton on Tempest side,
and now Tempest provides test_utils.call_until_true as the stable
library method. So this patch switches to use the stable method before
removing old test.call_until_true on Tempest side.

Change-Id: If8985f511d434af0449992b2bc3540da9b3a0591
1 file changed
tree: 12f51460f8435fe7052ad7b614e550b6f66f111c
  1. ceilometer/