DOC: Update license entries in metadata definitions

[HaoZeke]

Description

The existing example of a BSD license had an SPDX incompatible license entry (BSD) and also now links to the more informative example.yaml. These changes are in-line with the bot suggestions for new PRs (e.g. as seen here).

Checklist - did you ...

• Add a file to the news directory (using the template) for the next release's release notes?
  Doesn't seem like a big enough change, but I'd be happy to add to the news directory if required.
• Add / update necessary tests?
• Add / update outdated documentation?

[conda-bot]

We require contributors to sign our Contributor License Agreement and we don't have one on file for @HaoZeke.

In order for us to review and merge your code, please e-sign the Contributor License Agreement PDF. We then need to manually verify your signature, merge the PR (conda/infrastructure#791), and ping the bot to refresh the PR.

[HaoZeke]

@conda-bot refresh.

[github-actions]

Hi there, thank you for your contribution!

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed automatically if no further activity occurs.

If you would like this pull request to remain open please:

1. Rebase and verify the changes still work
2. Leave a comment with the current status

NOTE: If this pull request was closed prematurely, please leave a comment.

Thanks!

[HaoZeke]

@conda-bot refresh

[HaoZeke]

The annoyingly small documentation change is still relevant; and now there's a CLA on file as well.