tests: Fix bugs in test_compilation_and_rsync

This test suffered from two problems:
* git was failing beacuse it couldn't access configuration in /var/lib/jenkins
  directory using lizardfstest UID. I've added -H option to sudo to properly
  set the HOME environmental variable when running tests.
* using 'wait' instead of 'wait <jobspec>' wasn't able to generate a failure
  visible for Jenkins; vide man bash: "If n is not given, all currently active
  child processes are waited for, and the return status is zero."