Add a setPassword GraphQL mutation for setting a user's password (#2820)

* Feed `PasswordManager` through to the GraphQL `State`

* Add `setPassword` GraphQL mutation to update a user's password

crates/cli/src/commands/server.rs

@@ -200,6 +200,7 @@ impl Options {
             &policy_factory,
             homeserver_connection.clone(),
             site_config.clone(),
+            password_manager.clone(),
         );
 
         let state = {