Disable the default "podman pull" retry value. We use execd to retry
"podman create" on failure. Wihtout this change, a single container
can block start of other containers by 3 * 20 seconds. Now we only
block max 20 seconds before we try starting the next container.
Modern versions of podman (>= 5.0) have this --retry option, but it
does not have CNI, so this is a temporary workaround.
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>