message: Fix edge case in `Editor::backspace`
diff: @@ -47,8 +47,8 @@ impl<'a> Editor<'a> {
  pub fn backspace(&mut self) {
  match self.cursor.selection() {
  Some((start, end)) => {
  - self.value.remove_many(start, end);
  self.cursor.move_left(&self.value);
  + self.value.remove_many(start, end);
  }
  None => {
  let start = self.cursor.start(&self.value);
  @@ -64,9 +64,8 @@ impl<'a> Editor<'a> {
  pub fn delete(&mut self) {
  match self.cursor.selection() {
  - Some((start, end)) => {
  - self.value.remove_many(start, end);
  - self.cursor.move_left(&self.value);
  + Some(_) => {
  + self.backspace();
  }
  None => {
  let end = self.cursor.end(&self.value);
  