### Godot version

v4.1.stable.official [970459615]

### System information

Godot v4.1.stable - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce MX330 (NVIDIA; 30.0.15.1169) - 11th Gen Intel(R) Core(TM) i5-1135G7 @ 2.40GHz (8 Threads)

### Issue description

Calling `RichTextLabel`'s `select_all` method has no visual indicator, but it must have one. 

### Steps to reproduce

- Add `RichTextLabel` node
- Set `selection_enabled` value to be `true`
- Call `$RichTextLabel.select_all() `method in `_ready`

### Minimal reproduction project

[RichTextLabel_bug.zip](https://github.com/godotengine/godot/files/12098913/RichTextLabel_bug.zip)

ERR_FAIL_COND(theme_cache.normal_font.is_null());
	_push_def_font(NORMAL_FONT);
}
void RichTextLabel::push_bold() {
	ERR_FAIL_COND(theme_cache.bold_font.is_null());
	ItemFont *item_font = _find_font(current);
	_push_def_font((item_font && item_font->def_font == ITALICS_FONT) ? BOLD_ITALICS_FONT : BOLD_FONT);
}
void RichTextLabel::push_bold_italics() {
	ERR_FAIL_COND(theme_cache.bold_italics_font.is_null());
	_push_def_font(BOLD_ITALICS_FONT);
}
void RichTextLabel::push_italics() {
	ERR_FAIL_COND(theme_cache.italics_font.is_null());
	ItemFont *item_font = _find_font(current);
	_push_def_font((item_font && item_font->def_font == BOLD_FONT) ? BOLD_ITALICS_FONT : ITALICS_FONT);
}
void RichTextLabel::push_mono() {
	ERR_FAIL_COND(theme_cache.mono_font.is_null());
	_push_def_font(MONO_FONT);
}
void RichTextLabel::push_font_size(int p_font_size) {
	_stop_thread();
	MutexLock data_lock(data_mutex);
	ERR_FAIL_COND(current->type == ITEM_TABLE);
	ItemFontSize *item = memnew(ItemFontSize);
	item->font_size = p_font_size;
	_add_item(item, true);
}
void RichTextLabel::push_outline_size(int p_ol_size) {