Update outdated nsenter README content
Update outdated nsenter README content

Signed-off-by: Marco Vedovati <7ad294ca8ed51ab6f7b6cc42294ec572c85df1f5@suse.com>

opencontainers/runc,estesp/runc,opencontainers/runc,rhatdan/runc,rhatdan/runc,laijs/runc,rhatdan/runc,mheon/runc,adrianreber/runc,adrianreber/runc,estesp/runc,mYmNeo/runc,dqminh/runc,laijs/runc,xiaochenshen/runc,rhatdan/runc,mYmNeo/runc,xiaochenshen/runc,kolyshkin/runc,crosbymichael/runc,dqminh/runc,mheon/runc,mikebrow/runc,xiaochenshen/runc,adrianreber/runc,cyphar/runc,opencontainers/runc,cyphar/runc,estesp/runc,cyphar/runc,opencontainers/runc,justincormack/runc,kolyshkin/runc,dqminh/runc,mikebrow/runc,justincormack/runc,crosbymichael/runc,kolyshkin/runc,dqminh/runc,mikebrow/runc,mYmNeo/runc,crosbymichael/runc,justincormack/runc,kolyshkin/runc,laijs/runc,mheon/runc