Added mirror folder creation

Added mirror folder creation in the docker automation script

Depends-on: https://review.opendev.org/#/c/721517/

Story: 2007580
Task: 39501
Change-Id: Ib007fe30cf7a7632fa4df0a6664d7c2c09691781
Signed-off-by: Poornima <poornima.y.n@intel.com>

tb.sh

@@ -45,6 +45,8 @@ function exec_container {
 function run_container {
     # create localdisk
     mkdir -p ${LOCALDISK}/designer/${MYUNAME}/${PROJECT}
+    #create centOS mirror
+    mkdir -p ${HOST_MIRROR_DIR}/CentOS
 
     docker run -it --rm \
         --name ${TC_CONTAINER_NAME} \