Update Mercure bundle documentation

Fix Mercure Bundle config

Author: smnandre

src/Turbo/doc/index.rst

@@ -516,10 +516,15 @@ Otherwise, configure Mercure Hub(s) to use:
 
 .. code-block:: yaml
 
-    # config/packages/turbo.yaml
-    turbo:
-        mercure:
-            hubs: [default]
+    # config/packages/mercure.yaml
+    mercure:
+        hubs:
+            default:
+                url: '%env(MERCURE_URL)%'
+                public_url: '%env(MERCURE_PUBLIC_URL)%'
+                jwt:
+                    secret: '%env(MERCURE_JWT_SECRET)%'
+                    publish: '*'
 
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