ci: disable glcpp tests for now

these are too flaky to continue running for now

Signed-off-by: Yonggang Luo <luoyonggang@gmail.com>
Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/17928>

.gitlab-ci/meson/build.sh

@@ -68,6 +68,7 @@ meson _build --native-file=native.file \
       -D build-tests=false \
       -D c_args="$(echo -n $C_ARGS)" \
       -D cpp_args="$(echo -n $CPP_ARGS)" \
+      -D enable-glcpp-tests=false \
       -D libunwind=${UNWIND} \
       ${DRI_LOADERS} \
       ${GALLIUM_ST} \