Fix Read the Docs build error

[btjanaka]

Description

Read the Docs had an error due to sphinxcontrib-applehelp. This PR also makes a note to check Read the Docs before deploying in the future.

Status

• [x] I have read the guidelines in CONTRIBUTING.md
• [x] I have formatted my code using yapf
• [x] I have tested my code by running pytest
• [x] I have linted my code with pylint
• [N/A] I have added a one-line description of my change to the changelog in HISTORY.md
• [x] This PR is ready to go