Clippy with the current stable toolchain (#6615)

Fix lints that are coming with rust 1.64

Passes with the earlier toolchain from `rust-toolchain.toml` as well.

crates/nu-command/src/env/with_env.rs

@@ -110,7 +110,7 @@ fn with_env(
                 // primitive values([X Y W Z])
                 for row in table.chunks(2) {
                     if row.len() == 2 {
-                        env.insert(row[0].as_string()?, (&row[1]).clone());
+                        env.insert(row[0].as_string()?, row[1].clone());
                     }
                     // TODO: else error?
                 }