Issue #2226301 by alexpott: Run-test.sh --repeat should work nicely with --concurrency.

core/scripts/run-tests.sh

@@ -71,11 +71,14 @@
 
 simpletest_script_reporter_init();
 
-// Execute tests.
+$tests_to_run = array();
 for ($i = 0; $i < $args['repeat']; $i++) {
-  simpletest_script_execute_batch($test_list);
+  $tests_to_run = array_merge($tests_to_run, $test_list);
 }
 
+// Execute tests.
+simpletest_script_execute_batch($tests_to_run);
+
 // Stop the timer.
 simpletest_script_reporter_timer_stop();