docs: fix docs arrangement

[dandhlee]

Thank you for opening a Pull Request! Before submitting your PR, there are a few things you can do to make sure it goes smoothly:

• Make sure to open an issue as a bug/issue before writing your code! That way we can discuss the change, evaluate designs, and agree on the general idea
• Ensure the tests and linter pass
• Code coverage does not decrease (if any source code was changed)
• Appropriate docs were updated (if necessary)

Made some additional arrangements to help fix the docs generation for this library. Staged and spot checked to make sure the content is generated properly.

Googlers see the Buganizer entry below for preview links.

Fixes b/267202983 🦕