libobs: Update version to 31.0.1

[RytoEX]

Description

Update libobs version 31.0.1.

Motivation and Context

Update the version so we can release 31.0.1.

How Has This Been Tested?

It hasn't.

Types of changes

• Version Bump

Checklist:

• My code has been run through clang-format.
• I have read the contributing document.
• My code is not on the master branch.
• The code has been tested.
• All commit messages are properly formatted and commits squashed where appropriate.
• I have included updates to all appropriate documentation.