### 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.
int col = -1;
	if (p_key.length() > 0 && p_search.length() > 0) {
		if (p_from_column < 0 || p_from_column > p_search.length()) {
			p_from_column = 0;
		}
		while (col == -1 && p_from_column <= p_search.length()) {
			if (p_search_flags & SEARCH_MATCH_CASE) {
				col = p_search.find(p_key, p_from_column);
			} else {
				col = p_search.findn(p_key, p_from_column);
			}
			
			if (col != -1 && p_search_flags & SEARCH_WHOLE_WORDS) {
				p_from_column = col;
				if (col > 0 && !is_symbol(p_search[col - 1])) {
					col = -1;
				} else if ((col + p_key.length()) < p_search.length() && !is_symbol(p_search[col + p_key.length()])) {
					col = -1;
				}
			}
			p_from_column += 1;
		}
	}
	return col;
}
int TextEdit::_get_char_pos_for_line(int p_px, int p_line, int p_wrap_index) const {