Enable clippy::needless_question_mark (#8759)

This PR enables the
[`clippy::needless_question_mark`](https://rust-lang.github.io/rust-clippy/master/index.html#/needless_question_mark)
rule and fixes the outstanding violations.

Release Notes:

- N/A

crates/collab/src/api.rs

@@ -179,14 +179,13 @@ async fn add_contributor(
     Json(params): Json<AuthenticatedUserParams>,
     Extension(app): Extension<Arc<AppState>>,
 ) -> Result<()> {
-    Ok(app
-        .db
+    app.db
         .add_contributor(
             &params.github_login,
             params.github_user_id,
             params.github_email.as_deref(),
         )
-        .await?)
+        .await
 }
 
 #[derive(Deserialize)]

crates/collab/src/db/queries/rooms.rs

@@ -1030,7 +1030,7 @@ impl Database {
             if result.rows_affected != 1 {
                 Err(anyhow!("could not update room participant role"))?;
             }
-            Ok(self.get_room(room_id, &tx).await?)
+            self.get_room(room_id, &tx).await
         })
         .await
     }

crates/collab/src/db/tests/channel_tests.rs

@@ -43,7 +43,7 @@ async fn test_channels(db: &Arc<Database>) {
     let mut members = db
         .transaction(|tx| async move {
             let channel = db.get_channel_internal(replace_id, &tx).await?;
-            Ok(db.get_channel_participants(&channel, &tx).await?)
+            db.get_channel_participants(&channel, &tx).await
         })
         .await
         .unwrap();