testing: do not restart jobs too soon
testing: do not restart jobs too soon

If two testers can run the same jobs, they compete for recently started jobs if there
is nothing else left to do.  The right thing to do would be to move timeout handling
in the server, without needing intervention from the tester, and then you would not
need to pass back RUNNING tests in _find_applicable_test.  For now, just relieve the
pressure by not passing RUNNING tests until one hour has passed from the last attempt.

Signed-off-by: Paolo Bonzini <69d3ebcf5ee4e7f05a50dc23cd96655b730804b4@redhat.com>

pvital/patchew,pvital/patchew,pvital/patchew,pvital/patchew