UpdateVersionBranch: pass the App's ID as 'client-id' (#315)

Author: Paebbels

.github/workflows/UpdateVersionBranch.yml

@@ -63,9 +63,9 @@ on:
         default: 'update/'
       app_id:
         description: |
-          ID of a GitHub App with write access to contents, workflows and pull-requests. With 'app_private_key', the
-          job works with a token of that App instead of the workflow's own token, which can't push a change to a
-          file in '.github/workflows/'.
+          ID or Client ID of a GitHub App with write access to contents, workflows and pull-requests. With
+          'app_private_key', the job works with a token of that App instead of the workflow's own token, which can't
+          push a change to a file in '.github/workflows/'.
         type: string
         required: false
         default: ''
@@ -121,7 +121,7 @@ jobs:
         if: inputs.app_id != ''
         uses: actions/create-github-app-token@v3
         with:
-          app-id:                   ${{ inputs.app_id }}
+          client-id:                ${{ inputs.app_id }}
           private-key:              ${{ secrets.app_private_key }}
           permission-contents:      write
           permission-workflows:     write

doc/JobTemplate/Release/UpdateVersionBranch.rst

@@ -248,15 +248,17 @@ app_id
 :Type:            string
 :Required:        no
 :Default Value:   ``''``
-:Possible Values: The ID of a GitHub App, or empty.
+:Possible Values: The ID or the Client ID of a GitHub App, or empty.
 :Description:     ID of a GitHub App installed on the repository with write access to *Contents*, *Workflows* and
                   *Pull requests*. Together with :ref:`JOBTMPL/UpdateVersionBranch/Secret/app_private_key`, the job
                   creates a token of that App (:gh:`actions/create-github-app-token`) and uses it for all its steps.
                   |br|
                   The workflow's own ``GITHUB_TOKEN`` can't push a change to a file in :file:`.github/workflows/` -
                   no ``permissions:`` key grants that - so a release changing a workflow file needs the App. When
                   empty, the job uses ``GITHUB_TOKEN``. |br|
-                  The App ID isn't secret, so a repository variable is enough, e.g. ``${{ vars.RELEASE_APP_ID }}``.
+                  The job passes it as ``client-id`` to :gh:`actions/create-github-app-token`, which accepts both: GitHub
+                  takes the App ID and the Client ID as issuer of the App's token. Neither is secret, so a repository
+                  variable is enough, e.g. ``${{ vars.RELEASE_APP_ID }}``.
 
 
 .. _JOBTMPL/UpdateVersionBranch/Secrets: