Add missing tags to push rules endpoints

Without the tags, the endpoints don't end up in the swagger. No changelog for this because it doesn't affect the spec itself.

api/client-server/pushrules.yaml

@@ -498,6 +498,8 @@ paths:
                 type: boolean
                 description: Whether the push rule is enabled or not.
             required: ["enabled"]
+      tags:
+        - Push notifications
     put:
       summary: "Enable or disable a push rule."
       description: |-
@@ -601,6 +603,8 @@ paths:
                 items:
                   type: string
             required: ["actions"]
+      tags:
+        - Push notifications
     put:
       summary: "Set the actions for a push rule."
       description: |-