Enable clippy::search_is_some (#8748)

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

Release Notes:

- N/A

crates/editor/src/editor.rs

@@ -6444,10 +6444,9 @@ impl Editor {
                             && !movement::is_inside_word(&display_map, display_range.end))
                     {
                         // TODO: This is n^2, because we might check all the selections
-                        if selections
+                        if !selections
                             .iter()
-                            .find(|selection| selection.range().overlaps(&offset_range))
-                            .is_none()
+                            .any(|selection| selection.range().overlaps(&offset_range))
                         {
                             next_selected_range = Some(offset_range);
                             break;