docs: initial openedx -> edx.org changes

[robrap]

• remove unused github workflows.
• update logos for edx.org
• update openedx/edx-documentation urls to edx
• remove catalog-info.yml

Add a description of your changes with links to any relevant material.

Date Needed (optional)

If the release date of a feature is known or estimated, provide it to give reviewers guidance on turnaround time.

Reviewers

Possible roles follow. The PR submitter checks the boxes after each reviewer finishes and gives 👍.

• Subject matter expert:
• Subject matter expert:
• Product review:
• Partner support:
• PM review:

FYI: Tag anyone else who might be interested in this PR here.

Testing

• Ran ./run_tests.sh without warnings or errors

HTML Version (optional)

• Build an RTD draft for your branch and add a link here

Sandbox (optional)

• Point to or build a sandbox for the software change and add a link here

Post-review

• Add a comment with the description of this change or link this PR to the next release notes task.
• Squash commits