Add npm config restore after publish

[polnikale]

Fixes #15

Basically, after the "publishing" process is finished, we restore the .npmrc with the previous data.
Maybe it also makes sense adding a .prettierc to the package so that there are not so many changes

[mcous]

Thanks for this PR! After careful consideration and research, I decided it was best to take an alternative approach to solving this problem with #83. Rather than writing and restoring the user's .npmrc file, this module now writes and deletes an .npmrc file in a temporary location and points npm to that file. This is the approach that actions/setup-node uses, so I felt it was best to replicate that behavior in this action