OpenAPI: require all bodies in client-server

Signed-off-by: Lukas Lihotzki <lukas@lihotzki.de>

changelogs/client_server/newsfragments/3238.clarification

@@ -0,0 +1 @@
+Clarify that all request bodies are required.

data/api/client-server/receipts.yaml

@@ -61,6 +61,7 @@ paths:
           description: |-
             Extra receipt information to attach to `content` if any. The
             server will automatically set the `ts` field.
+          required: true
           schema:
             type: object
             example: {

data/api/client-server/report_content.yaml

@@ -49,6 +49,7 @@ paths:
           x-example: "$something:example.org"
         - in: body
           name: body
+          required: true
           schema:
             type: object
             example: {

data/api/client-server/room_send.yaml

@@ -65,6 +65,7 @@ paths:
           x-example: "35"
         - in: body
           name: body
+          required: true
           schema:
             type: object
             example: {

data/api/client-server/room_state.yaml

@@ -74,6 +74,7 @@ paths:
           x-example: "@alice:example.com"
         - in: body
           name: body
+          required: true
           schema:
             type: object
             example: {

data/api/client-server/users.yaml

@@ -47,6 +47,7 @@ paths:
       parameters:
         - in: body
           name: body
+          required: true
           schema:
             type: object
             properties: