resiliencytest.erp5: Fix ERP5 URL retrieve step

/reviewed-on !40

slapos/resiliencytest/suites/erp5.py

@@ -62,7 +62,7 @@ class ERP5TestSuite(SlaprunnerTestSuite):
     but connection parameter of what is inside of webrunner.
     """
     data = self._connectToSlaprunner(
-        resource='getConnectionParameter/slappart8'
+        resource='getConnectionParameter/slappart7'
     )
     url = json.loads(json.loads(data)['_'])['default-v6']
     self.logger.info('Retrieved erp5 url is:\n%s' % url)