Updated LineEdit to address #41278

Updated set_max_length() function to actually pull a substring of the current text so it's not all thrown away when the new max length is shorter than the current length.

(cherry picked from commit 71febfd6e2f6187fcc106ce715124cf173bfa0b8)

scene/gui/line_edit.cpp

@@ -1263,7 +1263,12 @@ void LineEdit::delete_text(int p_from_column, int p_to_column) {
 void LineEdit::set_text(String p_text) {
 
 	clear_internal();
-	append_at_cursor(p_text);
+
+	if (p_text.length() > max_length) {
+		append_at_cursor(p_text.substr(0, max_length));
+	} else {
+		append_at_cursor(p_text);
+	}
 
 	if (expand_to_text_length) {
 		minimum_size_changed();