Fix XML report

change stestr TO testr for correct xml report

Change-Id: I837ebd189a23745f874e07e8a7d09f92882fda97
diff --git a/bin/run_tempest.sh b/bin/run_tempest.sh
index f9852f6..d91a558 100755
--- a/bin/run_tempest.sh
+++ b/bin/run_tempest.sh
@@ -22,6 +22,6 @@
 tempest run $PATTERN | tee -a $log
 
 if [[ "$PATTERN" =~ '-r ' || "$PATTERN" =~ '--regex' || "$PATTERN" =~ '-s' ]]; then
-    stestr last --subunit | subunit2junitxml > $LOG_DIR/$report.xml
+    testr last --subunit | subunit2junitxml > $LOG_DIR/$report.xml
 fi