chore(users/Profpatsch): Move Multipart2 into new webstuff package

Change-Id: I903f1b554beed1240d2a9cf14ff44d1f3cb41ec5
Reviewed-on: https://cl.tvl.fyi/c/depot/+/9013
Tested-by: BuildkiteCI
Autosubmit: Profpatsch <mail@profpatsch.de>
Reviewed-by: Profpatsch <mail@profpatsch.de>

users/Profpatsch/whatcd-resolver/default.nix

@@ -9,12 +9,12 @@ let
 
     src = depot.users.Profpatsch.exactSource ./. [
       ./whatcd-resolver.cabal
-      ./src/Multipart2.hs
       ./src/WhatcdResolver.hs
     ];
 
     libraryHaskellDepends = [
       depot.users.Profpatsch.my-prelude
+      depot.users.Profpatsch.my-webstuff
       pkgs.haskellPackages.pa-prelude
       pkgs.haskellPackages.pa-label
       pkgs.haskellPackages.pa-json