Fix #143018: Assert browsing a non UTF8 render output path

Use copy_bytes_truncated when copying file paths which may not be UTF8.

Ref !144052

source/blender/blenkernel/intern/path_templates.cc

@@ -837,7 +837,7 @@ static blender::Vector<Error> eval_template(char *out_path,
                                             const VariableMap &template_variables)
 {
   if (out_path) {
-    in_path.copy_utf8_truncated(out_path, out_path_maxncpy);
+    in_path.copy_bytes_truncated(out_path, out_path_maxncpy);
   }
 
   const blender::Vector<Token> tokens = parse_template(in_path);