Add privilege escalation technique using LXD/LXC

[ArkaprabhaChakraborty]

Just came across this technique on a Hack the box machine. I guess it would be good to have it as a technique GTFOBins.
Some sources: https://book.hacktricks.xyz/linux-hardening/privilege-escalation/interesting-groups-linux-pe/lxd-privilege-escalation

[hoodietramp]

Oh just thought of adding it today, i rooted my own ubuntu with this 1

[hoodietramp]

lxd.md