Remove unused .netrc file from CircleCI (facebook#35785)

Summary:
Removing a stale configuration that was configuring username/password before publishing to NPM. This is effectively unused + the Github Token there is invalid therefore can be removed.

## Changelog

[INTERNAL] - Remove unused .netrc file from CircleCI

Pull Request resolved: facebook#35785

Test Plan: n/a

Reviewed By: cipolleschi

Differential Revision: D42385163

Pulled By: cortinico

fbshipit-source-id: 0dbbf44459d59f792da4221d6100800a2f4efda2

.circleci/config.yml

@@ -1495,10 +1495,6 @@ jobs:
               - equal: [ "nightly", << parameters.release_type >> ]
           steps:
             - run: echo "//registry.npmjs.org/:_authToken=${CIRCLE_NPM_TOKEN}" > ~/.npmrc
-            - run: |
-                git config --global user.email "react-native-bot@users.noreply.github.com"
-                git config --global user.name "npm Deployment Script"
-                echo "machine github.com login react-native-bot password $GITHUB_TOKEN" > ~/.netrc
       # END: Stables and nightlies
 
       - run: node ./scripts/publish-npm.js --<< parameters.release_type >>