Changes

kolaTestIso: retry failed tests

We've been seeing a lot of testiso flakes lately. Let's try to give
ourselves a break by retrying like we do for normal kola runs.

This is slightly different because it's not done inside kola but
outside kola. For the inside kola retry of testiso we'll wait for
https://github.com/coreos/coreos-assembler/issues/3989 to happen.

withPodmanRemote: drop the REMOTEUID in CONTAINER_HOST

I don't think this is needed anymore with [1]. See [2] [3].

[1] https://github.com/containers/podman/pull/23847
[2] https://github.com/containers/podman/issues/17452
[3] https://github.com/containers/podman/issues/23831