Show a warning when online k0s version defaulting fails #1247

Job	Run time
build	3m 4s
build-all	3m 55s
Basic dynamic config smoke (quay.io/k0sproject/bootloose-alpine3.18)	2m 44s
Basic 1+1 smoke using openssh client (quay.io/k0sproject/bootloose-alpine3.18)	1m 43s
Basic 1+1 smoke (quay.io/k0sproject/bootloose-alpine3.18)	2m 11s
Apply + backup + reset + restore (quay.io/k0sproject/bootloose-alpine3.18)	2m 36s
Basic 1+1 smoke (quay.io/k0sproject/bootloose-amazonlinux2023)	2m 20s
Basic file upload smoke (quay.io/k0sproject/bootloose-ubuntu20.04)	2m 36s
Apply + backup + reset + restore (quay.io/k0sproject/bootloose-rockylinux9)	2m 39s
Init sub-command smoke test	2m 17s
Basic 1+1 smoke (quay.io/k0sproject/bootloose-debian12)	2m 8s
Basic file upload smoke (quay.io/k0sproject/bootloose-alpine3.18)	2m 11s
Apply + backup + reset + restore (quay.io/k0sproject/bootloose-ubuntu20.04)	2m 35s
Basic 1+1 smoke (quay.io/k0sproject/bootloose-fedora38)	2m 22s
Basic 1+1 smoke (quay.io/k0sproject/bootloose-rockylinux9)	2m 22s
OS override smoke test	1m 42s
Basic 1+1 smoke (quay.io/k0sproject/bootloose-ubuntu20.04)	2m 14s
Apply + reset (quay.io/k0sproject/bootloose-rockylinux9)	2m 18s
Upgrade (quay.io/k0sproject/bootloose-alpine3.18, v1.21.6+k0s.0)	1m 50s
Apply + reset (quay.io/k0sproject/bootloose-ubuntu20.04)	2m 21s
Upgrade (quay.io/k0sproject/bootloose-amazonlinux2023, v1.21.6+k0s.0)	2m 47s
Upgrade (quay.io/k0sproject/bootloose-rockylinux9, v1.21.6+k0s.0)	2m 40s
Upgrade (quay.io/k0sproject/bootloose-ubuntu20.04, v1.21.6+k0s.0)	2m 26s
	56m 1s

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