Remove no longer used composer 1 package

I use shell.nix files for projects where I can pin the version.
But we also don't have any project with composer 1 anymore.

home/packages/composer1/composer.nix

@@ -1,34 +0,0 @@
-{ stdenv, fetchurl, makeWrapper, unzip, lib, php }:
-let
-  pname = "composer";
-  version = "1.10.26";
-in stdenv.mkDerivation {
-  inherit pname version;
-
-  src = fetchurl {
-    url = "https://getcomposer.org/download/${version}/composer.phar";
-    sha256 = "sha256-y/4fhSdsV6vkZNk0UD2TWqITSUrChidcjfq/qR49vcQ=";
-  };
-
-  dontUnpack = true;
-
-  nativeBuildInputs = [ makeWrapper ];
-
-  installPhase = ''
-    runHook preInstall
-    mkdir -p $out/bin
-    install -D $src $out/libexec/composer/composer.phar
-    makeWrapper ${php}/bin/php $out/bin/composer \
-      --add-flags "$out/libexec/composer/composer.phar" \
-      --prefix PATH : ${lib.makeBinPath [ unzip ]}
-    runHook postInstall
-  '';
-
-  meta = with lib; {
-    description = "Dependency Manager for PHP";
-    license = licenses.mit;
-    homepage = "https://getcomposer.org/";
-    changelog = "https://github.com/composer/composer/releases/tag/${version}";
-    maintainers = with maintainers; [ offline ] ++ teams.php.members;
-  };
-}

home/packages/composer1/default.nix

@@ -1,3 +0,0 @@
-self: super: {
-  composer1 = self.callPackage ./composer.nix { };
-}