fix: remove default value for NEXT_PUBLIC_API_URL in Dockerfile

Author: vuminhle1997

client-nachweise/Dockerfile

@@ -15,7 +15,7 @@ RUN if [ -f yarn.lock ]; then yarn install --frozen-lockfile; \
 COPY . .
 
 # Build the application
-ARG NEXT_PUBLIC_API_URL=http://localhost:8088
+ARG NEXT_PUBLIC_API_URL
 ENV NEXT_PUBLIC_API_URL=${NEXT_PUBLIC_API_URL}
 
 RUN npm run build || yarn build