tdf#39593 use existing clearConnectionPools() method

Change-Id: I318508531b3f52da2d699e6d35c7cda72d4de115
Reviewed-on: https://gerrit.libreoffice.org/68981
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
diff --git a/connectivity/source/cpool/ZPoolCollection.cxx b/connectivity/source/cpool/ZPoolCollection.cxx
index 7ae6603..ae32b27 100644
--- a/connectivity/source/cpool/ZPoolCollection.cxx
+++ b/connectivity/source/cpool/ZPoolCollection.cxx
@@ -437,11 +437,7 @@
        {
            m_aDriverProxies.clear();
            m_aDriverProxies = MapDriver2DriverRef();
            for(auto& rEntry : m_aPools)
            {
                rEntry.second->clear(false);
            }
            m_aPools.clear();
            clearConnectionPools(false);
        }
    }
    else if(evt.Source.is())