added slack secret support in CI/CD

Author: Himanshu Sharma

.github/workflows/deploy.yml

@@ -45,6 +45,7 @@ jobs:
           ECR_REGISTRY: ${{ steps.login-ecr.outputs.registry }}
           ECR_REPOSITORY: task-manager-api
           IMAGE_TAG: ${{ github.sha }}
+          SLACK_WEBHOOK_URL: ${{ secrets.SLACK_WEBHOOK_URL }}
         run: |
           docker build -t $ECR_REGISTRY/$ECR_REPOSITORY:$IMAGE_TAG .
           docker tag  $ECR_REGISTRY/$ECR_REPOSITORY:$IMAGE_TAG \