Override gar-image

Change gar-image to match the name we use in Docker Hub.

Author: martincostello

.github/workflows/ghcr-image-build-and-publish.yml

@@ -149,6 +149,7 @@ jobs:
         with:
           context: docker
           gar-environment: dev
+          gar-image: otel-lgtm
           gar-repository: "dockerhub-docker-otel-lgtm-dev-mirror/otel-lgtm"
           push: true
           platforms: linux/amd64,linux/arm64