update mi355x runners to add temp runners and remove nodes 0-3 (#203)

Author: cquil11

.github/configs/runners.yaml

@@ -39,9 +39,12 @@ mi325x:
 - 'mi325x-tw_2'
 - 'mi325x-tw_3'
 mi355x:
-- 'mi355x-amd_0'
-- 'mi355x-amd_1'
-- 'mi355x-amd_2'
-- 'mi355x-amd_3'
+# 0-3 undergoing maintenance, 4-5 are temporary nodes
+# - 'mi355x-amd_0'
+# - 'mi355x-amd_1'
+# - 'mi355x-amd_2'
+# - 'mi355x-amd_3'
+- 'mi355x-amd_4'
+- 'mi355x-amd_5'
 gb200:
 - gb200-nv_0