Let gh use github.token in "Collect expected failures"

This is to fix the error:

    gh: To use GitHub CLI in a GitHub Actions workflow, set the GH_TOKEN environment variable. Example:
      env:
        GH_TOKEN: ${{ github.token }}
    InvalidOperation: D:\a\_temp\ba9d92b7-3a94-4f7c-b541-d19003f40e19.ps1:9
    Line |
       9 |  $expected_failures = $match_info.Matches.Groups[1].Value -split "`n"  …
         |  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
         | Cannot index into a null array.
    Error: Process completed with exit code 1.

Author: EliahKagan

.github/workflows/ci.yml

@@ -110,6 +110,8 @@ jobs:
           Write-Output $actual_failures
           Set-Content -Path 'actual-failures.txt' -Value $actual_failures
       - name: Collect expected failures
+        env:
+          GH_TOKEN: ${{ github.token }}
         run: |
           $issue = 1358  # https://github.com/GitoxideLabs/gitoxide/issues/1358