Fix ui path for docker build

Author: gavlyukovskiy

.github/workflows/on-release-tag.yml

@@ -91,7 +91,7 @@ jobs:
             --build-arg VERSION=${VERSION} \
             -t ghcr.io/hackyourfuture/course-hub-frontend:${{ steps.get-version.outputs.version }} \
             -t ghcr.io/hackyourfuture/course-hub-frontend:latest \
-            .
+            ui
           if [ "$DOCKER_PUSH" = "true" ]; then
             docker push ghcr.io/hackyourfuture/course-hub-frontend:${{ steps.get-version.outputs.version }}
             docker push ghcr.io/hackyourfuture/course-hub-frontend:latest