Update .gitlab-ci.jsonnet

.gitlab-ci.jsonnet

-local dockerfile_name(image) = if image == "" then "Dockerfile" else "Dockerfile." + image; 
+local dockerfile_name(image) = if (image == "") then ("Dockerfile") else ("Dockerfile." + image); 
 local param_cmd(image) = {
         cmd: |||
             /kaniko/executor
@@ -6,7 +6,7 @@ local param_cmd(image) = {
             --dockerfile "${CI_PROJECT_DIR}/%(df)s"
             --destination "${CI_REGISTRY_IMAGE}/%(img)s:${CI_COMMIT_SHORT_SHA}"
             --destination "${CI_REGISTRY_IMAGE}/%(img)s:latest"
-        ||| % {img: image, df: dockerfile_name(df)},
+        ||| % {img: image, df: dockerfile_name(image)},
 };
 local param_job(image, depends=[]) = {
     stage: 'build',