improve konto-vue/Containerfile by explicitly stating images

kontor-vue/Containerfile

@@ -1,4 +1,4 @@
-FROM node:22.18.0-bookworm-slim AS build
+FROM docker.io/node:20-alpine AS build
 WORKDIR /app
 ENV PATH=/app/node_modules/.bin:$PATH
 COPY package.json /app/package.json
@@ -7,7 +7,7 @@ RUN npm install -g @vue/cli
 COPY . /app
 RUN npm run build
 
-FROM nginx:1.29.0-alpine
+FROM docker.io/library/nginx:stable-alpine
 COPY --from=build /app/dist /usr/share/nginx/html
 EXPOSE 80
 CMD ["nginx", "-g", "daemon off;"]