CI: Temporarily remove CS1000 configs from CI runs

Temporarily remove Corstone1000 from the configurations run
at nightly or per patch due to a known issue with the platform
that blocks us from performing the release merge back onto
master. To be re-enabled as soon as the Corstone1000 platform
recovers.

Signed-off-by: Antonio de Angelis <antonio.deangelis@arm.com>
Change-Id: I49b5e1bd572fb6e46f90fe84959319f1efd7e8d5
1 file changed