Improve install_command test

[gardar]

podman-gitlab-runner/prepare.sh

Lines 71 to 76 in 02d3f9e

	install_command() {
	# Run test if this binary exists
	PACKAGE=$1
	TEST_BINARY=$PACKAGE
	podman exec --user root:root "$CONTAINER_ID" /bin/bash -c 'if ! type '"$TEST_BINARY"' >/dev/null 2>&1; then

I think the install_command test could be improved as the packages listed under the dependencies don't all contain binaries that are equal to the name of the package.
The ca-certificates package for example does not contain any binary called ca-certificates (at least not on archlinux/debian/redhat) which causes the ca-certificates package to be installed in every job.
This can count for a significant amount of time, especially on yum based distros that have a lot of repos enabled.

Possible solutions:

• Adding a second argument to install_command for a file to check (or perhaps a command to run).
• Check if a package is installed instead of relying on the existence of a certain file/binary. This would need to be distro specific but it would be possible to use dpkg/rpm/etc. instead of apt/yum/dnf (using rpm is significantly faster than relying on yum/dnf).

[jonasbb]

It is indeed unfortunate that this always tries to install the package, but I am not aware how to check these things properly in a distro-agnostic version. Another problem I see is that the install command gets executed multiple times instead of installing all missing packages at once.
If someone wants to improve the situation, I am happy to merge that.