[AMD] feat: support multiple cluster for mi355x DI CI workflow

[billishyahao]

This patch is to support multiple cluster for MI355X distributed inference CI workflow.
This patch co-work with the branch sa-260114 of recipe https://github.com/billishyahao/sglang_disagg.git
Co-author: @ichbinblau

[billishyahao]

/sweep test-config --config-keys dsr1-fp8-mi355x-sglang-disagg --runner-config .github/configs/runners.yaml --config-files .github/configs/amd-master.yaml

[github-actions]

@billishyahao Kicking off a sweep.

Run: https://github.com/InferenceMAX/InferenceMAX/actions/runs/21024978364
Command: test-config --config-keys dsr1-fp8-mi355x-sglang-disagg --runner-config .github/configs/runners.yaml --config-files .github/configs/amd-master.yaml
Pinned ref: 654caea
Approval: not required (trusted collaborator).

[billishyahao]

/sweep test-config --config-keys dsr1-fp8-mi355x-sglang-disagg --runner-config .github/configs/runners.yaml --config-files .github/configs/amd-master.yaml

[github-actions]

@billishyahao Kicking off a sweep.

Run: https://github.com/InferenceMAX/InferenceMAX/actions/runs/21025811633
Command: test-config --config-keys dsr1-fp8-mi355x-sglang-disagg --runner-config .github/configs/runners.yaml --config-files .github/configs/amd-master.yaml
Pinned ref: 7fed049
Approval: not required (trusted collaborator).

[billishyahao]

17/18 cases succeeded and 1 failed. Should be an occasional occurence @cquil11 .https://github.com/InferenceMAX/InferenceMAX/actions/runs/21025811633

[billishyahao]

Use new PR https://github.com/InferenceMAX/InferenceMAX/pull/445. Close this.