Update action.yml

Using 'main' action will found 18 items. Like in tests 
SAMPLES_POST_CRED_COUNT: int = 18

.github/workflows/action.yml

@@ -34,7 +34,7 @@ jobs:
     - name: Prepare commit status
       run: |
         ITEMS_CNT=$(jq '. | length' output.json)
-        if [ 20 -eq ${ITEMS_CNT} ]; then
+        if [ 18 -eq ${ITEMS_CNT} ]; then
             echo "Samples were successfully scanned"
         else
             echo "Unexpected items: ${ITEMS_CNT}"