cleanup redundant pattern instances

Author: jogru0

std/src/path.rs

@@ -3265,7 +3265,7 @@ impl Hash for Path {
                 if !verbatim {
                     component_start += match tail {
                         [b'.'] => 1,
-                        [b'.', sep @ _, ..] if is_sep_byte(*sep) => 1,
+                        [b'.', sep, ..] if is_sep_byte(*sep) => 1,
                         _ => 0,
                     };
                 }