mailpit: move to pkgs/by-name

pkgs/by-name/ma/mailpit/package.nix

@@ -5,6 +5,7 @@
   nodejs,
   python3,
   libtool,
+  cctools,
   npmHooks,
   fetchFromGitHub,
   fetchNpmDeps,
@@ -28,6 +29,8 @@ let
     hash = source.hash;
   };
 
+  libtool' = if stdenv.hostPlatform.isDarwin then cctools else libtool;
+
   # Separate derivation, because if we mix this in buildGoModule, the separate
   # go-modules build inherits specific attributes and fails. Getting that to
   # work is hackier than just splitting the build.
@@ -43,7 +46,7 @@ let
     nativeBuildInputs = [
       nodejs
       python3
-      libtool
+      libtool'
       npmHooks.npmConfigHook
     ];
 

pkgs/top-level/all-packages.nix

@@ -3580,9 +3580,6 @@ with pkgs;
     };
   };
   mailnagWithPlugins = mailnag.withPlugins (builtins.attrValues mailnag.availablePlugins);
-  mailpit = callPackage ../servers/mail/mailpit {
-    libtool = if stdenv.hostPlatform.isDarwin then cctools else libtool;
-  };
 
   man = man-db;