postgresql: remove pipelinedb extension

This one is apparently abandoned by upstream and only supported
postgresql_11 which is about to be dropped from nixpkgs.

pkgs/servers/sql/postgresql/ext/pipelinedb.nix

@@ -1,38 +0,0 @@
-{ lib, stdenv, fetchFromGitHub, postgresql, zeromq, openssl, libsodium, libkrb5 }:
-
-stdenv.mkDerivation rec {
-  pname = "pipelinedb";
-  version = "1.0.0-13";
-
-  src = fetchFromGitHub {
-    owner = "pipelinedb";
-    repo = pname;
-    rev = version;
-    sha256 = "1mnqpvx6g1r2n4kjrrx01vbdx7kvndfsbmm7zbzizjnjlyixz75f";
-  };
-
-  buildInputs = [ postgresql openssl zeromq libsodium libkrb5 ];
-
-  makeFlags = [ "USE_PGXS=1" ];
-
-  NIX_LDFLAGS = lib.optionalString stdenv.isDarwin "-lsodium";
-
-  preConfigure = ''
-    substituteInPlace Makefile \
-      --replace "/usr/lib/libzmq.a" "${zeromq}/lib/libzmq.a"
-  '';
-
-  installPhase = ''
-    mkdir -p $out/bin
-    install -D -t $out/lib/ pipelinedb.so
-    install -D -t $out/share/postgresql/extension {pipelinedb-*.sql,pipelinedb.control}
-  '';
-
-  meta = with lib; {
-    description = "High-performance time-series aggregation for PostgreSQL";
-    homepage = "https://www.pipelinedb.com/";
-    license = licenses.asl20;
-    platforms = postgresql.meta.platforms;
-    maintainers = [ maintainers.marsam ];
-  };
-}

pkgs/servers/sql/postgresql/packages.nix

@@ -56,8 +56,6 @@ self: super: {
 
     pgtap = super.callPackage ./ext/pgtap.nix { };
 
-    pipelinedb = super.callPackage ./ext/pipelinedb.nix { };
-
     smlar = super.callPackage ./ext/smlar.nix { };
 
     temporal_tables = super.callPackage ./ext/temporal_tables.nix { };