Fixed not deselecting when clearing lineedit.

(cherry picked from commit bfba1e36bc3cb3f686f1fbbbb8187e26e28ef57f)

scene/gui/line_edit.cpp

@@ -1223,6 +1223,7 @@ void LineEdit::append_at_cursor(String p_text) {
 
 void LineEdit::clear_internal() {
 
+	deselect();
 	_clear_undo_stack();
 	cached_width = 0;
 	cursor_pos = 0;