Allowing these to grow infinitely leads to some really weird behaviors
when the enemy has been buying reserves long enough, where capturing a
base might result in 80 enemy vehicles suddenly at the gates.
This is just an interim fix. Ideally these units would be reinforcing
the front line as needed
(https://github.com/Khopa/dcs_liberation/issues/382), and a CP could be
lost without needing to completely destroy the defender.