remove new test and see if that's part of the problem (even though it isn't run before the failing test)

lib/spack/spack/test/concretize_preferences.py

@@ -179,22 +179,6 @@ def test_preferred_providers(self):
         spec = concretize("mpileaks")
         assert "zmpi" in spec
 
-    def test_config_set_url_for_package(self, mutable_mock_repo):
-        """Test preferred providers of virtual packages are
-        applied correctly
-        """
-        update_packages(
-            "mpileaks",
-            "package_attributes",
-            {"url": "http://www.somewhereelse.com/mpileaks-1.0.tar.gz"},
-        )
-        spec = concretize("mpileaks")
-        assert spec.package.fetcher[0].url == "http://www.somewhereelse.com/mpileaks-2.3.tar.gz"
-
-        update_packages("mpileaks", "package_attributes", {})
-        spec = concretize("mpileaks")
-        assert spec.package.fetcher[0].url == "http://www.llnl.gov/mpileaks-2.3.tar.gz"
-
     def test_preferred(self):
         """ "Test packages with some version marked as preferred=True"""
         spec = Spec("python")