remote server: Fix error log about inability to open buffer (#19824)

Turns out that we used client-side `fs` to check whether something is a
directory or not, which obviously doesn't work with SSH projects.

Release Notes:

- N/A

---------

Co-authored-by: Bennet <bennet@zed.dev>

crates/file_finder/src/file_finder.rs

@@ -790,9 +790,9 @@ impl FileFinderDelegate {
             let mut path_matches = Vec::new();
 
             let abs_file_exists = if let Ok(task) = project.update(&mut cx, |this, cx| {
-                this.abs_file_path_exists(query.path_query(), cx)
+                this.resolve_abs_file_path(query.path_query(), cx)
             }) {
-                task.await
+                task.await.is_some()
             } else {
                 false
             };