Is using cache for npm install in docker safe?

I was wondering about the point `8.1 Use multi-stage builds for leaner and more secure Docker images` and the example stated there:
```Dockerfile
FROM node:14.4.0 AS build

COPY . .
RUN npm ci && npm run build

FROM node:slim-14.4.0

USER node
EXPOSE 8080

COPY --from=build /home/node/app/dist /home/node/app/package.json /home/node/app/package-lock.json ./
RUN npm ci --production

CMD [ "node", "dist/app.js" ]
```
My idea here for speed up this build by using the cache:
```Dockerfile
FROM node:14.4.0 AS build

COPY . .
RUN npm ci --cache .npm --prefer-offline && npm run build

FROM node:slim-14.4.0

USER node
EXPOSE 8080

COPY --from=build /home/node/app/.npm ./.npm
COPY --from=build /home/node/app/dist /home/node/app/package.json /home/node/app/package-lock.json ./
RUN npm ci --production --cache .npm --prefer-offline

CMD [ "node", "dist/app.js" ]
```
But the only consideration that I have is `Is it safe`?

Start with section 8.1, “Use multi-stage builds for leaner and more secure Docker images,” and review the proposed Dockerfile alongside the existing example. Determine whether copying the npm cache between stages is safe, including any security or reproducibility concerns. Done means the documentation clearly answers the safety question and records relevant caveats.

Written by the indexing model from the issue text.