fix error checking if netns exists (#47397)
fix error checking if netns exists (#47397)

This patch fixes an error that occurs when attempting to see if the
netns already exists on the remote device.  This change will now execute
`ip netns list` and check if the desired namespace is in the output.

Signed-off-by: Peter Sprygada <c9a100a965edf1325bb001a738a9001c889d4efc@ansible.com>
thaim/ansible,thaim/ansible