Add rustfmt skip to default frame benchmarking template (#9473)

This was missed in the introduction pr of rustfmt. There we only had
updated the Substrate local template.

substrate/utils/frame/benchmarking-cli/src/template.hbs

 {{header}}
-//! Autogenerated weights for {{pallet}}
+//! Autogenerated weights for `{{pallet}}`
 //!
 //! THIS FILE WAS AUTO-GENERATED USING THE SUBSTRATE BENCHMARK CLI VERSION {{version}}
 //! DATE: {{date}}, STEPS: `{{cmd.steps}}`, REPEAT: {{cmd.repeat}}, LOW RANGE: `{{cmd.lowest_range_values}}`, HIGH RANGE: `{{cmd.highest_range_values}}`
@@ -10,6 +10,7 @@
 // {{arg}}
 {{/each}}
 
+#![cfg_attr(rustfmt, rustfmt_skip)]
 #![allow(unused_parens)]
 #![allow(unused_imports)]