test: skip dbstat test unless we're using our packaged libraries

because system libraries may not have this enabled

test/test_database.rb

@@ -729,6 +729,8 @@ def test_sqlite_dbpage_vtab
     end
 
     def test_dbstat_table_exists
+      skip("dbstat not supported") unless SQLite3::SQLITE_PACKAGED_LIBRARIES
+
       assert_nothing_raised { @db.execute("select * from dbstat") }
     end
   end