fix(npmrc): merge .npmrc in user's homedir and project

[jiawei397]

This PR will merge project and user's homedir .npmrc

• per-project config file (/path/to/my/project/.npmrc)
• per-user config file (~/.npmrc)

Normally, after logging in using npm, the token is stored in the user's home, and in the current project, we only need to switch the image to avoid the key being submitted.

Such as the user home dir .npmrc:

@denotest:registry=http://localhost:4261/
//localhost:4261/:_authToken=private-reg-token
@denotest2:registry=http://localhost:4262/
//localhost:4262/:_authToken=private-reg-token2

the project .npmrc just be :

@denotest:registry=http://localhost:4261/
@denotest2:registry=http://localhost:4262/

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