Merge pull request #19265 from shamser/issue32934

HPCC-32934 Capture and report starting timings for ExternalActivity

Reviewed-by: Jake Smith <jake.smith@lexisnexisrisk.com>
Merged-by: Gavin Halliday <ghalliday@hpccsystems.com>

thorlcr/activities/external/thexternalslave.cpp

@@ -79,6 +79,7 @@ class CExternalSlaveActivity : public CSlaveActivity
     }
     virtual void start() override
     {
+        ActivityTimer t(slaveTimerStats, timeActivities);
         //Cannot call base base start because that will error if > 1 input
         startAllInputs();
         dataLinkStart();