[ROCm][CI] Setting some mi325_4 tests back to optional (in parity with upstream) (#37711)

Signed-off-by: Andreas Karatzas <akaratza@amd.com>

.buildkite/test-amd.yaml

@@ -1745,6 +1745,7 @@ steps:
   timeout_in_minutes: 106
   mirror_hardwares: [amdexperimental, amdproduction, amdgfx942nightly, amdmi325]
   agent_pool: mi325_4
+  optional: true
   working_dir: "/vllm-workspace/tests"
   source_file_dependencies:
   - vllm/
@@ -2550,6 +2551,7 @@ steps:
   mirror_hardwares: [amdexperimental, amdproduction, amdgfx942nightly, amdmi325]
   agent_pool: mi325_4
   num_gpus: 4
+  optional: true
   working_dir: "/vllm-workspace/tests"
   source_file_dependencies:
   - vllm/
@@ -2665,6 +2667,7 @@ steps:
   mirror_hardwares: [amdexperimental, amdproduction, amdgfx942nightly, amdmi325]
   agent_pool: mi325_4
   num_gpus: 4
+  optional: true
   working_dir: "/vllm-workspace/.buildkite/lm-eval-harness"
   source_file_dependencies:
   - csrc/
@@ -2685,6 +2688,7 @@ steps:
   mirror_hardwares: [amdexperimental, amdproduction, amdgfx942nightly, amdmi325]
   agent_pool: mi325_4
   num_gpus: 4
+  optional: true
   working_dir: "/vllm-workspace/.buildkite/lm-eval-harness"
   source_file_dependencies:
   - csrc/
@@ -2750,6 +2754,7 @@ steps:
   mirror_hardwares: [amdexperimental, amdproduction, amdgfx942nightly, amdmi325]
   agent_pool: mi325_4
   num_gpus: 4
+  optional: true
   working_dir: "/vllm-workspace"
   source_file_dependencies:
   - vllm/model_executor/models/
@@ -2792,6 +2797,7 @@ steps:
   timeout_in_minutes: 11
   mirror_hardwares: [amdexperimental, amdproduction, amdgfx942nightly, amdmi325]
   agent_pool: mi325_4
+  optional: true
   working_dir: "/vllm-workspace"
   source_file_dependencies:
   - vllm/model_executor/models/
@@ -2813,6 +2819,7 @@ steps:
   mirror_hardwares: [amdexperimental, amdproduction, amdgfx942nightly, amdmi325]
   agent_pool: mi325_4
   num_gpus: 4
+  optional: true
   working_dir: "/vllm-workspace"
   source_file_dependencies:
   - vllm/model_executor/models/