action: Fix using deprecated GitHub auth API

Fixes the following deprecation warning:

action.py:457: DeprecationWarning: Argument login_or_token is deprecated, please use auth=github.Auth.Token(…) instead

action-manifest

This respository contains a GitHub action implemented in Python to partially automate west-based manifest workflows.

It currently performs the following tasks:

Parses the PR changes to detect if the manifest file has been modified
Constructs both the old manifest (the one in the PR base SHA) and the new manifest (the one in the tip of the PR) and compares them
Adds a set of DNM labels when one or more of the revision: fields in the manifest point to a Pull Request
Adds a set of labels to be associated with a change to the manifest
Adds a set of per-manifest project with the format {prefix}{project_name}
Posts and updates a message with a revision comparison table

See action.yml for a full list of options.