Auto merge of #110806 - WaffleLapkin:unmkI, r=lcnr

Replace `tcx.mk_trait_ref` with `TraitRef::new`

First step in implementing https://github.com/rust-lang/compiler-team/issues/616
r? `@lcnr`

compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs

@@ -191,7 +191,7 @@ impl<'tcx> ConstToPat<'tcx> {
             self.tcx(),
             ObligationCause::dummy(),
             self.param_env,
-            self.tcx().mk_trait_ref(partial_eq_trait_id, [ty, ty]),
+            ty::TraitRef::new(self.tcx(), partial_eq_trait_id, [ty, ty]),
         );
 
         // FIXME: should this call a `predicate_must_hold` variant instead?