Bad credentials error when using mode github_action

[nkolov]

Description

When using the GitHub action to generate a diagram in mode="github_action", I get the following error

Flow to UML is now running...
Failed to update GitHub comments: Error: Failed to fetch pull request review comments: Bad credentials - https://docs.github.com/rest
    at GithubClient.getAllCommentsForPullRequest (https://jsr.io/@goog/flow-lens/0.1.12/src/main/github_client.ts:166:13)
    at eventLoopTick (ext:core/01_core.js:178:7)
    at async UmlWriter.writeGithubComment (https://jsr.io/@goog/flow-lens/0.1.12/src/main/uml_writer.ts:74:32)
    at async UmlWriter.writeUmlDiagrams (https://jsr.io/@goog/flow-lens/0.1.12/src/main/uml_writer.ts:54:7)
error: Uncaught (in promise) Error: Failed to fetch pull request review comments: Bad credentials - https://docs.github.com/rest
      throw new Error(
            ^
    at GithubClient.getAllCommentsForPullRequest (https://jsr.io/@goog/flow-lens/0.1.12/src/main/github_client.ts:166:13)
    at eventLoopTick (ext:core/01_core.js:178:7)
    at async UmlWriter.writeGithubComment (https://jsr.io/@goog/flow-lens/0.1.12/src/main/uml_writer.ts:74:32)
    at async UmlWriter.writeUmlDiagrams (https://jsr.io/@goog/flow-lens/0.1.12/src/main/uml_writer.ts:54:7)
Error: Process completed with exit code 1.

Expected behavior

The authentication should pass and this error shouldn't appear.

Additional details

The code for the Github action is the following, basically the one from the official example -

name: Pull Request Add Flow Lens

on:
  pull_request:
    branches:
      - testing
      - preprod
      - main

jobs:
  add_flow_lens:
    name: Add Flow Lens to a PR that has added or changed flows
    runs-on: [ raas-azure-shared ]
    permissions: write-all
    outputs:
      changed_flows: ${{ steps.changed-files.outputs.flows_any_changed }}

    steps:
      - uses: actions/checkout@v3

      # Collect all flow files that have been modified in this PR
      - name: Get changed files of last push
        id: changed-files
        uses: tj-actions/changed-files@v46.0.1
        with:
          files_yaml: |
            flows:
              - force-app/main/default/flows/**

      
      # Check if any flows files are changed, and print the result
      - name: Print changes from previous step
        id: print-changes
        if: steps.changed-files.outputs.flows_any_changed == 'true'
        env:
          CHANGED_FLOW_FILES: ${{ steps.changed-files.outputs.flows_all_changed_files }}
        run: |
          echo "Number of changes flow(s): ${{ steps.changed-files.outputs.flows_all_changed_files_count }}"
          for file in ${CHANGED_FLOW_FILES}; do
            echo "$file was updated"
          done

  create_graph:
    name: Add Flow Lens Graph if changed flows
    needs: add_flow_lens
    if: needs.add_flow_lens.outputs.changed_flows == 'true'
    permissions: write-all
    runs-on: [ raas-azure-shared ]
    steps:
      - uses: actions/checkout@v3
        with:
          ref: ${{ github.ref }}
          fetch-depth: 2

      # Install deno and cache installation package used by Flow Lens GitHub Action
      - name: Install and cache deno
        id: deno-install
        uses: denoland/setup-deno@v2
        with:
          deno-version: latest
          cache: true
      
      # Generate flow diagrams
      - name: Generate flow diagrams
        run: |
          deno run \
            --allow-read \
            --allow-write \
            --allow-env \
            --allow-net \
            --allow-run \
            jsr:@goog/flow-lens \
            --mode="github_action" \
            --diagramTool="mermaid" \
            --gitDiffFromHash="HEAD^1" \
            --gitDiffToHash="HEAD"
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

It is using a custom runner on an own company GitHub server. The runners can be Linux and Windows based, I get the same error with both.