Fix deprecated set-output use in ci.yml

Author: Alenar

.github/workflows/ci.yml

@@ -485,7 +485,7 @@ jobs:
 
     - name: Get short SHA
       id: slug
-      run: echo "::set-output name=sha8::$(echo ${{ github.sha }} | cut -c1-7)"
+      run: echo "sha8=$(echo ${{ github.sha }} | cut -c1-7)" >> $GITHUB_OUTPUT
 
     - name: Setup Terraform
       uses: hashicorp/setup-terraform@v2