remove unnecessary displayname requirement on making user admin

Signed-off-by: strawberry <strawberry@puppygock.gay>

src/admin/user/commands.rs

@@ -373,20 +373,12 @@ pub(super) async fn force_leave_room(
 #[admin_command]
 pub(super) async fn make_user_admin(&self, user_id: String) -> Result<RoomMessageEventContent> {
 	let user_id = parse_local_user_id(self.services, &user_id)?;
-	let displayname = self
-		.services
-		.users
-		.displayname(&user_id)?
-		.unwrap_or_else(|| user_id.to_string());
 
 	assert!(
 		self.services.globals.user_is_local(&user_id),
 		"Parsed user_id must be a local user"
 	);
-	self.services
-		.admin
-		.make_user_admin(&user_id, displayname)
-		.await?;
+	self.services.admin.make_user_admin(&user_id).await?;
 
 	Ok(RoomMessageEventContent::notice_markdown(format!(
 		"{user_id} has been granted admin privileges.",

src/api/client/account.rs

@@ -347,10 +347,7 @@ pub(crate) async fn register_route(
 	if !is_guest {
 		if let Some(admin_room) = services.admin.get_admin_room()? {
 			if services.rooms.state_cache.room_joined_count(&admin_room)? == Some(1) {
-				services
-					.admin
-					.make_user_admin(&user_id, displayname)
-					.await?;
+				services.admin.make_user_admin(&user_id).await?;
 
 				warn!("Granting {user_id} admin privileges as the first user");
 			}

src/service/admin/grant.rs

@@ -21,7 +21,7 @@ impl super::Service {
 	/// Invite the user to the conduit admin room.
 	///
 	/// In conduit, this is equivalent to granting admin privileges.
-	pub async fn make_user_admin(&self, user_id: &UserId, displayname: String) -> Result<()> {
+	pub async fn make_user_admin(&self, user_id: &UserId) -> Result<()> {
 		let Some(room_id) = self.get_admin_room()? else {
 			return Ok(());
 		};
@@ -65,7 +65,7 @@ impl super::Service {
 					event_type: TimelineEventType::RoomMember,
 					content: to_raw_value(&RoomMemberEventContent {
 						membership: MembershipState::Join,
-						displayname: Some(displayname),
+						displayname: None,
 						avatar_url: None,
 						is_direct: None,
 						third_party_invite: None,