eo_test_manager_xattr: Fix resource leak

Summary:
Coverity reports that we leak the eina_binbuf returned from
eina_value_to_binbuf function, so add a call to eina_binbuf_free.

Fixes CID1400953

@fix

Depends on D8762

Reviewers: raster, cedric, zmike, bu5hm4n, segfaultxavi

Reviewed By: segfaultxavi

Subscribers: segfaultxavi, #reviewers, #committers

Tags: #efl

Differential Revision: https://phab.enlightenment.org/D8769

src/tests/eio/eio_test_manager_xattr.c

@@ -80,11 +80,13 @@ _future_done_cb(void *data EINA_UNUSED,
         fail_if(!buf);
         fail_if(strcmp((const char*) eina_binbuf_string_get(buf),
                        attr_data[i]) != 0);
+        eina_binbuf_free(buf);
      }
 
    fail_if((int) i != total_attributes);
 
    ecore_main_loop_quit();
+
    return array;
 }