### Godot version

4.1

### System information

Windows

### Issue description

Being able to have multiple cursors similarly to vscode is a great feature, however it's only possible to add carets, not remove them. By left clicking you can remove all extra cursors but you cannot remove a specific one so after selecting multiple lines a single missclick, you have to reselect them all again. Looking at the original pr there was a remove_caret function added so it would make sense to be able to remove carets when clicking again, like in vscode.

![image](https://github.com/godotengine/godot/assets/19669673/3867c00e-9faa-4429-9c6d-f2d6d3883044)


### Steps to reproduce

- Alt click to add multiple carets
- Alt click on the same position again
- Nothing happens

### Minimal reproduction project

N/A
if (p_line < 0 || p_line >= text.size()) {
		return "";
	}
	return text[p_line];
}
int TextEdit::get_line_width(int p_line, int p_wrap_index) const {
	ERR_FAIL_INDEX_V(p_line, text.size(), 0);
	ERR_FAIL_COND_V(p_wrap_index > get_line_wrap_count(p_line), 0);
	return text.get_line_width(p_line, p_wrap_index);
}
int TextEdit::get_line_height() const {
	return MAX(text.get_line_height() + theme_cache.line_spacing, 1);
}
int TextEdit::get_indent_level(int p_line) const {
	ERR_FAIL_INDEX_V(p_line, text.size(), 0);
	int tab_count = 0;
	int whitespace_count = 0;
	int line_length = text[p_line].size();
	for (int i = 0; i < line_length - 1; i++) {
		if (text[p_line][i] == '\t') {
			tab_count++;
		} else if (text[p_line][i] == ' ') {
			whitespace_count++;
		} else {
			break;
		}
	}
	return tab_count * text.get_tab_size() + whitespace_count;
}
int TextEdit::get_first_non_whitespace_column(int p_line) const {