build: add GitHub token to auto-start-ci workflow

Recent changes to node-core-utils attempt to read pull request labels
when deciding whether or not to start a V8 CI. This requires a valid
GitHub token with appropriate permissions to be set for node-core-utils.

Refs: nodejs/node-core-utils#652
PR-URL: #45185
Fixes: #45163
Reviewed-By: Jiawen Geng <technicalcute@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>

Author: richardlau

.github/workflows/auto-start-ci.yml

@@ -60,7 +60,7 @@ jobs:
       - name: Setup node-core-utils
         run: |
           ncu-config set username ${{ secrets.JENKINS_USER }}
-          ncu-config set token none
+          ncu-config set token "${{ secrets.GH_USER_TOKEN }}"
           ncu-config set jenkins_token ${{ secrets.JENKINS_TOKEN }}
           ncu-config set owner "${{ github.repository_owner }}"
           ncu-config set repo "$(echo ${{ github.repository }} | cut -d/ -f2)"