update TC_IT_MESH_EST.yml and TC_IT_MESH_COMM.yml
change mesh ci case form T50 to T12 in gitlab-ci.yml
add some test ENV in components/idf_test/integration_test/TEST_ENV_SSC.yml
Currently CI test environment is complicated, usually includes NIC, AP.
These devices are not used for a lot test cases. Therefore we split the
test environment, remove unnecessary devices. Then it will be easier to
create CI runners.