Update Clippy and fix lints (#932)

Author: newpavlov

.github/workflows/workspace.yml

@@ -20,7 +20,7 @@ jobs:
       - uses: RustCrypto/actions/cargo-cache@master
       - uses: dtolnay/rust-toolchain@master
         with:
-          toolchain: 1.67.0 # Pinned to prevent breakages
+          toolchain: 1.71.0 # Pinned to prevent breakages
           components: clippy
       - run: cargo clippy --all --all-features -- -D warnings
 

fiat-constify/src/main.rs

@@ -146,7 +146,7 @@ fn rewrite_fn_as_const(func: &mut ItemFn, type_registry: &TypeRegistry) {
 fn rewrite_fn_body(statements: &[Stmt], outputs: &Outputs, registry: &TypeRegistry) -> Block {
     let mut stmts = Vec::new();
 
-    stmts.extend(outputs.to_let_bindings(registry).into_iter());
+    stmts.extend(outputs.to_let_bindings(registry));
 
     for stmt in statements {
         let mut stmt = stmt.clone();