In tests, give Ganeti enough time to actually start up jobs before
asserting that they succeed. While normally forking and executing
a job is finished in less than a second in some circumstances it
can take longer; so give enough time to avoid flaky tests.

While there, also pause the watcher, so that it doesn't submit
jobs inbetween that cause our 0.01 second delay jobs to take
longer while waiting for locks taken by the watcher's jobs.

Signed-off-by: Klaus Aehlig <aehlig@google.com>
Reviewed-by: Petr Pudlak <pudlak@google.com>