openapi: better handle nested schemas

there is a 2 levels schemas in profile.notifications.

The code previously assumed we could only have one level, and so was not
producing the correct UsersProfileNotifications.

Fix that by being more generic in the way we retrieve the nested
subschemas.

public/api/wekan.yml

@@ -3681,20 +3681,6 @@ definitions:
       - createdAt
       - modifiedAt
       - authenticationMethod
-  UsersEmails:
-    type: object
-    properties:
-      address:
-        description: |
-           The email address
-        type: string
-      verified:
-        description: |
-           Has the email been verified
-        type: boolean
-    required:
-      - address
-      - verified
   UsersProfile:
     type: object
     properties:
@@ -3750,14 +3736,6 @@ definitions:
         type: array
         items:
           $ref: "#/definitions/UsersProfileNotifications"
-      activity:
-        description: |
-           The id of the activity this notification references
-        type: string
-      read:
-        description: |
-           the date on which this notification was read
-        type: string
       showCardsCountAt:
         description: |
            showCardCountAt field of the user
@@ -3813,7 +3791,6 @@ definitions:
            Reference to the board templates swimlane Id
         type: string
     required:
-      - activity
       - templatesBoardId
       - cardTemplatesSwimlaneId
       - listTemplatesSwimlaneId
@@ -3829,3 +3806,30 @@ definitions:
         description: |
            last hit that was returned
         type: number
+  UsersEmails:
+    type: object
+    properties:
+      address:
+        description: |
+           The email address
+        type: string
+      verified:
+        description: |
+           Has the email been verified
+        type: boolean
+    required:
+      - address
+      - verified
+  UsersProfileNotifications:
+    type: object
+    properties:
+      activity:
+        description: |
+           The id of the activity this notification references
+        type: string
+      read:
+        description: |
+           the date on which this notification was read
+        type: string
+    required:
+      - activity