add variablesTest.yml for testing purposes

.github/workflows/variablesTest.yml

@@ -0,0 +1,36 @@
+name: Test env variables
+on:
+  workflow_dispatch:
+  pull_request:
+  push:
+
+env: 
+  DOCKER_IMAGE_TAG: :refs_heads_${{ github.ref_name }}-bk0
+
+jobs:
+  check_event:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      - name: Echo variables
+        run: |
+          echo ${{ env.DOCKER_IMAGE_TAG }}
+          echo ${{ github.event_name }}
+      
+      - name: Check for DOCKER_IMAGE_TAG change
+        if: GITHUB_EVENT_NAME == 'pull_request'
+        run: echo ":refs_heads_${GITHUB_HEAD_REF}-bk0" >> $env.DOCKER_IMAGE_TAG
+
+      - name: Echo DOCKER_IMAGE_TAG again
+        run: echo ${{ env.DOCKER_IMAGE_TAG }}
+
+  check_permanence:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+
+      - name: Echo DOCKER_IMAGE_TAG again
+        run: echo ${{ env.DOCKER_IMAGE_TAG }}