configure_rabbitmq: Specifically handle VHost 404 (#241)

Our current configuration doesn't actually specify vhost, so if you are
trying to configure a fresh RabbitMQ then you will get apparently
mysterious failures.

HISTORY.rst

@@ -4,6 +4,7 @@ History
 
 Unreleased
 ----------
+* ``zocalo.configure_rabbitmq``: Show explicit error when VHost not created.
 
 0.30.2 (2023-09-06)
 -------------------

src/zocalo/cli/configure_rabbitmq.py

@@ -458,6 +458,13 @@ def run():
                 permanent_bindings.append(b)
         update_config(api, binding_specs, permanent_bindings)
     except requests.exceptions.HTTPError as e:
+        # Specially handle the VHost error, as we used to not setup vhosts
+        try:
+            if e.response.json()["reason"] == "vhost_not_found":
+                logger.error(f"Error 404: VHost not found for url: {e.response.url}")
+                sys.exit(1)
+        except Exception:
+            raise
         logger.error(e)
         sys.exit(1)