Add new actions editor::FindNextMatch and editor::FindPreviousMatch (#28559)

Closes #7903

Release Notes:

- Add new actions `editor::FindNextMatch` and
`editor::FindPreviousMatch` that are similar to `editor::SelectNext` and
`editor::SelectPrevious` with `"replace_newest": true`, but jumps to the
first or last selection when there are multiple selections.

assets/keymaps/macos/sublime_text.json

@@ -51,7 +51,9 @@
       "cmd-shift-j": "editor::JoinLines",
       "shift-alt-m": "markdown::OpenPreviewToTheSide",
       "ctrl-backspace": "editor::DeleteToPreviousWordStart",
-      "ctrl-delete": "editor::DeleteToNextWordEnd"
+      "ctrl-delete": "editor::DeleteToNextWordEnd",
+      "cmd-g": "editor::FindNextMatch",
+      "cmd-shift-g": "editor::FindPreviousMatch"
     }
   },
   {