Use release-environment project id instead of canonical

What does this MR do and why?

• Update update_merge_requests_label.rb to use release-environments project ID instead of canonical.
• Use COM_RELEASE_TOOLS_BOT for PAT instead of PROJECT_TOKEN_FOR_CI_SCRIPTS_API_USAGE

References

Related https://gitlab.com/gitlab-com/gl-infra/delivery/-/issues/21484

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