[master] Clear components dict as documented in BoB.kill_started_components()

This issue was detected post-merge, and seems to have been introduced
by commit 86ed7ae9cfb4184f5637a2e478242f0a646ba2e1 in master.

src/bin/bind10/bind10_src.py.in

@@ -338,6 +338,7 @@ class BoB:
         """
         logger.info(BIND10_KILLING_ALL_PROCESSES)
         self.__kill_children(True)
+        self.components = {}
 
     def _read_bind10_config(self):
         """