testing/k3s: fix cni path, build server, add alternative bin

7 jobs for !11646 with k3s in 14 minutes and 18 seconds (queued for 1 second)
detached
Status Job ID Name Coverage
  Lint
passed lint #191381
docker-alpine x86_64

00:00:26

 
  Build
passed build-aarch64 #191386
docker-alpine ci-build aarch64

00:02:04

passed build-armv7 #191387
docker-alpine ci-build armv7

00:03:48

passed build-ppc64le #191385
docker-alpine ci-build ppc64le

00:08:36

passed build-s390x #191384
docker-alpine ci-build s390x

00:02:22

passed build-x86 #191383
docker-alpine ci-build x86

00:01:50

passed build-x86_64 #191382
docker-alpine ci-build x86_64

00:13:52