autotest: add timeout for reboot_dut_for_shard_deletion.

BUG=chromium:705166
TEST=Run unittest.

Change-Id: If63cd5e0a4f158a71ab1dce27ee1d30cfedebf46
Reviewed-on: https://chromium-review.googlesource.com/462335
Commit-Ready: Xixuan Wu <xixuan@chromium.org>
Tested-by: Xixuan Wu <xixuan@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>
diff --git a/frontend/afe/rpc_interface.py b/frontend/afe/rpc_interface.py
index b2e7efe..e17a72c 100644
--- a/frontend/afe/rpc_interface.py
+++ b/frontend/afe/rpc_interface.py
@@ -2110,7 +2110,9 @@
                 'reboot_dut_for_shard_deletion',
                 priority=priorities.Priority.SUPER,
                 control_type='Server',
-                control_file=c, hosts=hostnames_to_lock)
+                control_file=c, hosts=hostnames_to_lock,
+                timeout_mins=10,
+                max_runtime_mins=10)
 
     # Unlock these shard-related hosts.
     dicts = {'locked': False, 'lock_time': None}