Example Dockerfile does not copy .npmc / .yarnrc files

Verify canary release

• I verified that the issue exists in the latest Next.js canary release

Provide environment information

Operating System:
  Platform: win32
  Arch: x64
  Version: Windows 11 Pro
  Available memory (MB): 32566
  Available CPU cores: 16
Binaries:
  Node: 20.12.2
  npm: N/A
  Yarn: N/A
  pnpm: 9.10.0
Relevant Packages:
  next: 14.2.10 // An outdated version detected (latest is 15.0.1), upgrade is highly recommended!
  eslint-config-next: N/A
  react: 18.3.1
  react-dom: 18.3.1
  typescript: 5.5.4
Next.js Config:
  output: standalone

Which example does this report relate to?

with-docker

What browser are you using? (if relevant)

No response

How are you deploying your application? (if relevant)

No response

Describe the Bug

Currently example Dockerfile does not try to copy .npmrc / .yarnrc files which can lead to issues when installing packages

Expected Behavior

Example Dockerfile should attempt to copy those configuration files just like it attempts to copy the lock files

To Reproduce

1. Add a package from a private registry to your NextJS project
2. Copy the example Dockerfile into your project
3. Attempt to build the docker image

Start by opening the Dockerfile for the with-docker example and compare how it handles lock files with the package-manager configuration files named in the issue. Verify the example can build a project that uses a private registry, and consider the work complete when those configuration files are handled during the image build.