### Godot version

4.0 beta 15

### System information

Windows 10

### Issue description

It happened with both Google IME and MS-IME, and there was no problem until Beta14.
When typing Japanese characters, it is common to select a character from the suggestion window and then start typing the next character before confirming.
In this case, uncommitted characters are forcibly committed, and input of the next character begins.

**↓Beta15**

https://user-images.githubusercontent.com/186786/214753450-b493cca6-2644-4b3d-8cd2-660565cc3547.mp4

**↓Beta14**

https://user-images.githubusercontent.com/186786/214755127-dde819cc-4d63-403a-99b0-09821671f74e.mp4



### Steps to reproduce

It happened with both Google IME and MS-IME in beta15

### Minimal reproduction project

It is project independent and happens in the editor.
if (!selecting_enabled || !is_multiple_carets_enabled()) {
		return;
	}
	if (text.size() == 1 && text[0].length() == 0) {
		return;
	}
	
	
	int caret = get_caret_count() - 1;
	if (!has_selection(caret)) {
		select_word_under_caret(caret);
		return;
	}
	const String &highlighted_text = get_selected_text(caret);
	int column = get_selection_from_column(caret) + 1;
	int line = get_caret_line(caret);
	const Point2i next_occurrence = search(highlighted_text, SEARCH_MATCH_CASE, line, column);
	if (next_occurrence.x == -1 || next_occurrence.y == -1) {
		return;
	}
	int to_column = get_selection_to_column(caret) + 1;
	int end = next_occurrence.x + (to_column - column);
	int new_caret = add_caret(next_occurrence.y, end);
	if (new_caret != -1) {
		select(next_occurrence.y, next_occurrence.x, next_occurrence.y, end, new_caret);
		adjust_viewport_to_caret(new_caret);
		merge_overlapping_carets();
	}
}
void TextEdit::select(int p_from_line, int p_from_column, int p_to_line, int p_to_column, int p_caret) {