make additions to tshooting guide

[hellt]

add to the tshoot page the commands to:

• stop & remove stale clab containers
• remove file in /var/run/netns/clab* & /var/run/netns/containerlab*
• remove docker networks for created by clab and bridges
• check if tx-offload is disabled

[hellt]

will need to be re-evaluated based on users response and framed in a form of a tshoot/faq article