ci: Add 'latest' tag to images built from main

Signed-off-by: Phoevos Kalemkeris <[email protected]>

Author: phoevos

.github/workflows/docker.yaml

@@ -68,6 +68,7 @@ jobs:
             type=semver,pattern={{major}}.{{minor}}
             type=semver,pattern={{major}}
             type=sha
+            type=raw,value=latest,enable={{is_default_branch}}
 
       - name: Build and push ${{ matrix.service }}
         uses: docker/build-push-action@v6