chore: Make clearer in the example that the fallback prefix sequence should be repeated for each line

Signed-off-by: Samuel Loury <konubinixweb@gmail.com>

changelogs/client_server/newsfragments/1690.clarification

@@ -0,0 +1 @@
+Make clearer in the example that the fallback prefix sequence should be repeated for each line.

content/client-server-api/modules/rich_replies.md

@@ -60,7 +60,8 @@ specific fallback text is different for each `msgtype`, however the
 general format for the `body` is:
 
 ```text
-> <@alice:example.org> This is the original body
+> <@alice:example.org> This is the first line of the original body
+> This is the second line
 
 This is where the reply goes
 ```