Update hash used as **.

Author: gkellogg

lib/rdf/spec/mutable.rb

@@ -56,7 +56,7 @@
       end
 
       it "should accept an optional hash argument" do
-        expect { subject.load(RDF::Spec::TRIPLES_FILE, {}) }.not_to raise_error
+        expect { subject.load(RDF::Spec::TRIPLES_FILE, **{}) }.not_to raise_error
       end
 
       it "should load statements" do