CI/CD: add timeout

Author: mrogowski

.github/workflows/main.yml

@@ -16,6 +16,7 @@ jobs:
       matrix:
         shmem: [sos_ubuntu, sos_fedora, oshmem_ubuntu, oshmem_fedora, oshmpi_ubuntu, oshmpi_fedora, osss_ubuntu, osss_fedora]
     runs-on: ubuntu-latest
+    timeout-minutes: 30
     steps:
       - name: Checkout
         uses: actions/checkout@v3