Increase test timeout to 60

I am seeing jobs unstable because they hit the timeout

stack-info: PR: #697, branch: jansel/stack/153

Author: jansel

.github/workflows/test.yml

@@ -113,4 +113,4 @@ jobs:
           if [[ "${{ matrix.dtype-asserts }}" == "true" ]]; then export HELION_DEBUG_DTYPE_ASSERTS=1; fi
           if [[ "${{ matrix.expecttest-accept }}" == "true" ]]; then export EXPECTTEST_ACCEPT=1; fi
           if [[ "${{ matrix.ref-eager }}" == "true" ]]; then export HELION_INTERPRET=1; fi
-          pytest --timeout=30
+          pytest --timeout=60