remove tmp release flag and set trigger to release published

Author: Alex Melnyk

.github/workflows/publish_layer.yml

@@ -1,9 +1,8 @@
 name: Publish lambda layer to SAR
 
 on:
-  push:
-    branches:
-      - feat/lambda-layers
+  release:
+    types: [published]
 env:
   AWS_ACCESS_KEY_ID: ${{ secrets.AWS_ACCESS_KEY_ID }}
   AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
@@ -20,7 +19,6 @@ jobs:
         echo ::set-env name=RELEASE_TAG_VERSION::${RELEASE_TAG_VERSION:1}
     - name: write version to ssm
       run: |
-        RELEASE_TAG_VERSION=1.3.0 # simulate release here, will be removed later
         aws ssm put-parameter --name "powertools-python-release-version" --value $RELEASE_TAG_VERSION --overwrite
     - name: trigger lamber layer publish pipeline
       run: |