agl-session: remove agl-driver user from applaunchd group

agl-session: remove agl-driver user from applaunchd group

Previously agl-driver user was part of applaunchd group for D-Bus activation
to work woth the correct access rights. Now that D-Bus activation has been
removed from applaunchd, agl-driver user no longer needs to be in the same
group with applaunchd.

Bug-AGL: SPEC-4801

Change-Id: Ia473b391432d8c797cd38c0841f7fe655dcdb8e6
Signed-off-by: Denys Dmytriyenko <denys@konsulko.com>
Reviewed-on: https://gerrit.automotivelinux.org/gerrit/c/AGL/meta-agl/+/28930
Reviewed-by: Scott Murray <scott.murray@konsulko.com>
Reviewed-by: Jan-Simon Moeller <jsmoeller@linuxfoundation.org>
Tested-by: Jenkins Job builder account
ci-image-build: Jenkins Job builder account
ci-image-boot-test: Jenkins Job builder account