ci: setup npm authentication for publish (microsoft#2422)

## Summary:

`nx release` requires a `.npmrc` file. Let's create one with our NPM
auth token, and remove it after we finish publishing out of an abundance
of caution.

## Test Plan:

Change is already in 0.76-stable and 0.77-stable. For whatever reason,
it works on 0.76 and not on 0.77

---------

Co-authored-by: Tommy Nguyen <4123478+tido64@users.noreply.github.com>

Author: Saadnajmi

.ado/templates/npm-publish-steps.yml

@@ -26,10 +26,24 @@ steps:
 
   - script: |
       git switch $(Build.SourceBranchName)
+      echo "//registry.npmjs.org/:_authToken=$(NODE_AUTH_TOKEN)" > ~/.npmrc
       yarn nx release --skip-publish --verbose
-      yarn nx release publish --excludeTaskDependencies
     env:
       GITHUB_TOKEN: $(githubAuthToken)
+    displayName: Version Packages and Github Release
+    condition: and(succeeded(), eq(variables['publish_react_native_macos'], '1'))
+
+  - script: |
+      echo "//registry.npmjs.org/:_authToken=$(NODE_AUTH_TOKEN)" > ~/.npmrc
+      yarn nx release publish --excludeTaskDependencies
+    env:
       NODE_AUTH_TOKEN: $(npmAuthToken)
-    displayName: Version and publish packages
+    displayName: Publish packages
     condition: and(succeeded(), eq(variables['publish_react_native_macos'], '1'))
+
+  - script: |
+      rm -f ~/.npmrc
+    env:
+      NODE_AUTH_TOKEN: $(npmAuthToken)
+    displayName: Remove npmrc if it exists
+    condition: always()