update std++

opam.pins

-coq-stdpp https://gitlab.mpi-sws.org/robbertkrebbers/coq-stdpp 3103b7bf52d0275f2938d9af44ab2d0db89a6251
+coq-stdpp https://gitlab.mpi-sws.org/robbertkrebbers/coq-stdpp 0671cb48dd1f893c48672de216847d46d5263e04

theories/algebra/ofe.v

@@ -222,9 +222,7 @@ Ltac f_contractive :=
   end;
   try reflexivity.
 
-Ltac solve_contractive :=
-  preprocess_solve_proper;
-  solve [repeat (first [f_contractive|f_equiv]; try eassumption)].
+Ltac solve_contractive := solve_proper_core ltac:(fun _ => first [f_contractive | f_equiv]).
 
 (** Fixpoint *)
 Program Definition fixpoint_chain {A : ofeT} `{Inhabited A} (f : A → A)