Fix several tests that did not appropriately use the vic-admin env var

[mhagen-vmware]

[skip unit]
[specific ci=23-02-VCH-List --suite 24-01-Multi-VCH-PS --suite 24-02-Multi-VCH-Delete --suite 6-13-TLS]

1. remove the empty vch list test, that needs to be re-implemented in our nightlies otherwise we can never run parallel jobs
2. make sure to set VIC-ADMIN in the multi-vch tests so that gather logs will work
3. update the docker params with the newer VCH installed

[rajanashok]

lgtm

[zjs]

remove the empty vch list test, that needs to be re-implemented in our nightlies otherwise we can never run parallel jobs

Could we file an issue to track re-introducing this?

[mhagen-vmware]

#7880