bitbake: cooker: Ensure any existing hashserv connection is closed

Ensure any exiting hash server connection is terminated before we start
a new bitbake session. This avoids errors seen with memory resident bitbake
when the asyncio event loop isn't closed correctly.

(Bitbake rev: 42ff9de77f24e2a0bec48a14b64c4b538e00b4af)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/cooker.py

@@ -1766,6 +1766,8 @@ class BBCooker:
         self.state = state.initial
 
     def reset(self):
+        if hasattr(bb.parse, "siggen"):
+            bb.parse.siggen.exit()
         self.initConfigurationData()
         self.handlePRServ()