Fix the framework order for each continuous benchmarking run (#10109)

The environment variable values used by system services are
not persistent, so any changes to them are lost after services
finish execution. As a result, the framework order was not
toggled properly after each continuous benchmarking run
completed. Instead, use a regular file to keep track of the
order.

Signed-off-by: Anton Kirilov <antonvkirilov@proton.me>

Author: volyrique

toolset/continuous/tfb-startup.sh

@@ -20,10 +20,12 @@ git clone \
 echo "moving to tfb directory"
 cd $TFB_REPOPARENT/$TFB_REPONAME
 
-if [ -z "$TFB_RUN_ORDER" ]; then
+if [ -e "${TFB_REPOPARENT}/tfb-reverse-order" ]; then
   export TFB_RUN_ORDER="reverse"
+  sudo rm -rf "${TFB_REPOPARENT}/tfb-reverse-order"
 else
   unset TFB_RUN_ORDER
+  touch "${TFB_REPOPARENT}/tfb-reverse-order"
 fi
 
 echo "building tfb docker image"