Also, allow to check the transition message after the dialog to make sure, and
retry if the check fails and the maximum number of attempts is not 1.

This way, it is possible to confirm an object and check that it has been
confirmed in only one call including retries.

It was involving twisted conversion back and forth between
erp5.util.testbrowser which expected the URL and ERP5 site id whereas
erp5.util.benchmark which only expected the full URL.

Moreover, it was not working if there is no "real" ERP5 site ID, for example
with: http://foobar.org/.

It is more consistent with existing naming within erp5.util and
zope.testbrowser parent module as well.