[JIRA] (OVIRT-1831) Make `global-setup.sh` check if packages are installed before trying to install them

Make `global-setup.sh` check if packages are installed before trying to install them ------------------------------------------------------------------------------------ Key: OVIRT-1831 URL: https://ovirt-jira.atlassian.net/browse/OVIRT-1831 Project: oVirt - virtualization made easy Issue Type: Improvement Components: Jenkins Slaves Reporter: Barak Korren Assignee: infra The way '{{global-setup.sh}}' works currently is that it tries to install all the packages it needs in a single yum command and then runs in a loop and checks if the packages were installed properly. If the packages are already installed this takes a negligible amount of time on CentOS slaves, but on Fedora it seems to take much longer and as much as 2 minutes. We should try to make '{{global-setup.sh}}' faster by making it not try to install packages before checking if they are there, but instead check first and only try to install the missing ones. Note that if we'll install multiple packages in a single command, we'll still need to verify they were properly installed after the yum/dnf command finishes.