replacing new access token with configured token from npmrc

[jpg619]

get flatOptions method is used to fetch all the configuration data including tokens.

The const { list } = this.config object used to fetch current access token + configured token written in the .npmrc file.

const tokenList = [] array is used for collecting the tokens from list.
Using iteration methods instead of filter and map to avoid Object Object complexity.

const flatKeyPair is used to identify key pair from const { flat } = this.config.

tokenList[1] will be avail if any active token written inside .npmrc file. if avail then replace with that.

References

Fixes #3888