(MAINT) Removed unused trapperkeeper-authorization doc reference
(MAINT) Removed unused trapperkeeper-authorization doc reference

This commit removes an unused reference to trapperkeeper-authorization
from the release_notes.markdown.

rlinehan/puppetserver,er0ck/puppetserver,briancain/puppet-server,rlinehan/puppetserver,rlinehan/puppetserver,camlow325/puppetserver,rlinehan/puppet-server,puppetlabs/puppetserver,camlow325/puppetserver,shrug/puppet-server,waynr/puppetserver,cprice404/puppetserver,shrug/puppet-server,rlinehan/puppetserver,er0ck/puppetserver,briancain/puppet-server,erikPrime/puppetserver,cprice404/puppet-server,shrug/puppet-server,cprice404/puppet-server,erikPrime/puppet-server,camlow325/puppet-server,cprice404/puppet-server,waynr/puppet-server,puppetlabs/puppetserver,puppetlabs/puppetserver,waynr/puppetserver,camlow325/puppet-server,erikPrime/puppet-server,rlinehan/puppet-server,shrug/puppet-server,puppetlabs/puppet-server,waynr/puppetserver,camlow325/puppetserver,waynr/puppet-server,puppetlabs/puppet-server,puppetlabs/puppetserver,erikPrime/puppet-server,cprice404/puppetserver,briancain/puppet-server,erikPrime/puppetserver,er0ck/puppetserver,puppetlabs/puppet-server,camlow325/puppetserver,camlow325/puppet-server,er0ck/puppetserver,erikPrime/puppetserver,waynr/puppet-server,cprice404/puppetserver,rlinehan/puppet-server