CI: Increase setup timeout to 20min, add timestamps

- Increase qemu-1-setup.sh timeout to 20min since it sometimes
  fails to complete after 15min.

- Timestamp all qemu-1-setup.sh lines to look for hangs.

- Add a 'watchdog' process to print out the top running process every
  30sec to help with debugging.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #17714

.github/workflows/zfs-qemu.yml

@@ -77,8 +77,12 @@ jobs:
         ref: ${{ github.event.pull_request.head.sha }}
 
     - name: Setup QEMU
-      timeout-minutes: 15
-      run: .github/workflows/scripts/qemu-1-setup.sh
+      timeout-minutes: 20
+      run: |
+        # Add a timestamp to each line to debug timeouts
+        while IFS=$'\n' read -r line; do
+            echo "$(date +'%H:%M:%S') $line"
+        done < <(.github/workflows/scripts/qemu-1-setup.sh)
 
     - name: Start build machine
       timeout-minutes: 10