Add rustfmt::skip to the msg_target template

Author: tnull

fuzz/src/msg_targets/msg_target_template.txt

@@ -10,6 +10,8 @@
 // This file is auto-generated by gen_target.sh based on msg_target_template.txt
 // To modify it, modify msg_target_template.txt and run gen_target.sh instead.
 
+#![cfg_attr(rustfmt, rustfmt_skip)]
+
 use crate::msg_targets::utils::VecWriter;
 use crate::utils::test_logger;