test/helpers: remove logging of if ExecPodCmd failed
test/helpers: remove logging of if ExecPodCmd failed

ExecPodCmd logged to console at error level if a command failed. Sometimes, an
error is expected from the provided command to the function, which emits error
logs to console. Since the function already returns an error, which tests can
decide if they want to assert being nil or not, remove the logging of the
failure of the command to console.

Signed-off by: Ian Vernon <ian@cilium.io>

tgraf/cilium,tgraf/cilium,michi-covalent/cilium,eloycoto/cilium,michi-covalent/cilium,michi-covalent/cilium,scanf/cilium,cilium/cilium,michi-covalent/cilium,tgraf/cilium,cilium/cilium,cilium/cilium,scanf/cilium,tklauser/cilium,eloycoto/cilium,scanf/cilium,scanf/cilium,tgraf/cilium,cilium-team/cilium,scanf/cilium,cilium/cilium,scanf/cilium,tklauser/cilium,tgraf/cilium,cilium-team/cilium,eloycoto/cilium,cilium/cilium,eloycoto/cilium,scanf/cilium,tgraf/cilium,tklauser/cilium,eloycoto/cilium,eloycoto/cilium,eloycoto/cilium,tklauser/cilium,michi-covalent/cilium,tklauser/cilium