pkg/k8s: fix custom dialer logic for etcd >= 3.5.0
pkg/k8s: fix custom dialer logic for etcd >= 3.5.0

Since etcd >= 3.5.0 the library started to remove the URL Scheme from
the URL making the custom dialer failing parse a "service ID" from the
URL. This commit introduces some logic that will allow it to parse a
"service ID" from the URL that doesn't have the URL Scheme, as per
etcd 3.5.0.

Signed-off-by: André Martins <bc9800b9d52a24cce72a73dd528afed53f10e5fc@cilium.io>

cilium/cilium,michi-covalent/cilium,michi-covalent/cilium,cilium/cilium,michi-covalent/cilium,cilium/cilium,michi-covalent/cilium,cilium/cilium,michi-covalent/cilium,cilium/cilium