guile-lib: Disable a test which doesn't work with Guile 2.2

Error is:

    ERROR: In procedure %resolve-variable:
    ERROR: Unbound variable: use-syntax
    FAIL: sxml.ssax.scm

Also add pkg-config so that configure script can find libguile.

Relevant to #28643

pkgs/development/guile-modules/guile-lib/default.nix

@@ -1,4 +1,4 @@
-{stdenv, fetchurl, guile, texinfo}:
+{stdenv, fetchurl, guile, texinfo, pkgconfig}:
 
 assert stdenv ? cc && stdenv.cc.isGNU;
 
@@ -10,8 +10,14 @@ stdenv.mkDerivation rec {
     sha256 = "1f9n2b5b5r75lzjinyk6zp6g20g60msa0jpfrk5hhg4j8cy0ih4b";
   };
 
+  nativeBuildInputs = [pkgconfig];
   buildInputs = [guile texinfo];
 
+  # One test doesn't seem to be compatible with guile_2_2
+  patchPhase = ''
+    sed -i -e '/sxml.ssax.scm/d' unit-tests/Makefile*
+  '';
+
   doCheck = true;
 
   preCheck =