Remove unnecessary parts from link

Co-authored-by: Hubert Chathi <hubertc@matrix.org>

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

@@ -102,7 +102,7 @@ of the characters `[0-9a-zA-Z._~-]`.
 (Note that this matches the grammar of 'opaque IDs' from
 [MSC1597](https://github.com/matrix-org/matrix-spec-proposals/blob/rav/proposals/id_grammar/proposals/1597-id-grammar.md#opaque-ids),
 and that of the `id` property of the
- [`m.login.sso` flow schema](https://spec.matrix.org/v1.5/client-server-api/#definition-mloginsso-flow-schema).)
+ [`m.login.sso` flow schema](#definition-mloginsso-flow-schema).)
 
 #### Behaviour on Room Leave
 If the client sees the user it is in a call with leave the room, the client should treat this