Add SciPy 2022 talk to presentations

[maxrjones]

Description of proposed changes

Adds a link to the SciPy talk in the overview page.

Fixes #

Reminders

• [ ] Run make format and make check to make sure the code follows the style guide.
• [ ] Add tests for new features or tests that would have caught the bug that you're fixing.
• [ ] Add new public functions/methods/classes to doc/api/index.rst.
• [ ] Write detailed docstrings for all functions/methods.
• [ ] If wrapping a new module, open a 'Wrap new GMT module' issue and submit reasonably-sized PRs.
• [ ] If adding new functionality, add an example to docstrings or tutorials.

Slash Commands

You can write slash commands (/command) in the first line of a comment to perform specific operations. Supported slash commands are:

• /format: automatically format and lint the code
• /test-gmt-dev: run full tests on the latest GMT development version

[seisman]

Nice presentation!

For this PR, I feel the thumbnail image doc/_static/scipy2022-youtube-thumbnail.png is too large (834 KB) and should not be included in the repo.

[seisman]

For this PR, I feel the thumbnail image doc/_static/scipy2022-youtube-thumbnail.png is too large (834 KB) and should not be included in the repo.

The thumbnail image can be compressed to less than 100 KB using https://squoosh.app/.