Add new test start_from_startup.py to just see that the device can boot from startup config

Useful to run in a loop.

test/case/misc/start_from_startup.py

@@ -0,0 +1,38 @@
+#!/usr/bin/env python3
+
+import infamy
+from infamy.util import wait_boot
+import copy
+
+def remove_config(target):
+    running = target.get_config_dict("/ietf-hardware:hardware")
+    new = copy.deepcopy(running)
+    new["hardware"].clear()
+    target.put_diff_dicts("ietf-hardware",running,new)
+
+with infamy.Test() as test:
+    with test.step("Initialize"):
+        env = infamy.Env(infamy.std_topology("1x1"))
+        target = env.attach("target", "mgmt")
+
+    with test.step("Configure"):
+        target.put_config_dict("ietf-system", {
+            "system": {
+                "hostname": "test"
+            }
+        })
+        remove_config(target)
+        target.copy("running", "startup")
+    with test.step("Reboot and wait for the unit to come back"):
+        target.copy("running", "startup")
+        target.reboot()
+        if wait_boot(target) == False:
+            test.fail()
+        target = env.attach("target", "mgmt", factory_default = False)
+
+    with test.step("Verify hostname"):
+        data = target.get_dict("/ietf-system:system/hostname")
+        print(data)
+        assert(data["system"]["hostname"] == "test")
+
+    test.succeed()