Enable clippy::identity_op (#8773)

This PR enables the
[`clippy::identity_op`](https://rust-lang.github.io/rust-clippy/master/index.html#/identity_op)
rule and fixes the outstanding violations.

Release Notes:

- N/A

crates/languages/src/ocaml.rs

@@ -140,7 +140,7 @@ impl LspAdapter for OCamlLspAdapter {
                 }
 
                 let mut label_highlight = vec![(
-                    0..0 + label.len(),
+                    0..label.len(),
                     language.grammar()?.highlight_id_for_name("property")?,
                 )];