Leave no apk cache in the Docker image

This will make the Docker image tidier

Dockerfile

@@ -6,11 +6,11 @@ RUN npm ci && npm run tsc
 
 FROM node:16-alpine as app
 WORKDIR /usr/src/app
-RUN apk add git postgresql-client
+RUN apk add --no-cache git postgresql-client
 COPY --from=builder ./node_modules ./node_modules
 COPY --from=builder ./dist ./dist
 COPY ./.git ./.git
 COPY entrypoint.sh .
 COPY databases/*.sql databases/
 EXPOSE 8080
-CMD ./entrypoint.sh
+CMD ./entrypoint.sh