[Tests] Remove rocky8 from released tests

Signed-off-by: Enrico Usai <usai@amazon.com>

Author: enrico-usai

tests/integration-tests/configs/released.yaml

@@ -262,7 +262,7 @@ test-suites:
       dimensions:
         - regions: [ "ap-east-1" ]
           instances: {{ common.INSTANCES_DEFAULT_X86 }}
-          oss: {{ common.NOT_RELEASED_OSES }}
+          oss: ["alinux2"]
           schedulers: [ "slurm" ]
     test_slurm.py::test_slurm_memory_based_scheduling:
       dimensions: