Rollup merge of #72109 - matthiaskrgr:cl8ppy, r=Dylan-DPC

Fix clippy warnings

Fixes clippy::{cone_on_copy, filter_next, redundant_closure, single_char_pattern, len_zero,redundant_field_names, useless_format, identity_conversion, map_clone, into_iter_on_ref, needless_return, option_as_ref_deref, unused_unit, unnecessary_mut_passed}

r? @Dylan-DPC

src/librustc_query_system/dep_graph/dep_node.rs

@@ -80,7 +80,7 @@ impl<K: DepKind> DepNode<K> {
             }
         }
 
-        return dep_node;
+        dep_node
     }
 }
 

src/librustc_query_system/dep_graph/mod.rs

@@ -77,9 +77,9 @@ pub trait DepKind: Copy + fmt::Debug + Eq + Ord + Hash {
         OP: FnOnce() -> R;
 
     /// Access dependencies from current implicit context.
-    fn read_deps<OP>(op: OP) -> ()
+    fn read_deps<OP>(op: OP)
     where
-        OP: for<'a> FnOnce(Option<&'a Lock<TaskDeps<Self>>>) -> ();
+        OP: for<'a> FnOnce(Option<&'a Lock<TaskDeps<Self>>>);
 
     fn can_reconstruct_query_key(&self) -> bool;
 }