Title: #829: ci: disable timeout
There is a bug in jenkins  which causes to include the time a job is
waiting for an available executor is added to the complete execution time.
As a consequence a job may time out without actually started because it
did not get the executor in time.
Therefore we disable the timeout completely. We can abort it manually if
a job hangs for some reason. The job always finished so far but many jobs
were aborted because they were waiting for an executor for a long time.
To pull the PR as Git branch:
git remote add ghsssd https://github.com/SSSD/sssd
git fetch ghsssd pull/829/head:pr829
git checkout pr829