The [compute] change_password_available parameter was renamed in 2013
by d5c9602bee0b9366bca1f118379f196a794ed907 but the corresponding
parameter in puppet-tempest was not updated and still configuring
the old, unused parameter.
This change deprecates the parameter because it has has no effect for
a long time.
Closes-Bug: #1958511
Change-Id: I11ed3c7014b9c14bbbd1a08f98d3aa2dd947f74e