Update pipeline.yml

Set the timeout for AMDGPU to be more generous for now

Author: kshyatt

.buildkite/pipeline.yml

@@ -36,7 +36,7 @@ steps:
       rocm: "*"
       rocmgpu: "*"
     if: build.message !~ /\[skip tests\]/
-    timeout_in_minutes: 60
+    timeout_in_minutes: 90
     matrix:
       setup:
         julia: