Set combo box button type

[rmainwork]

Describe your changes

Added button type to combo box dropdown. This prevents the button from accidentally submitting the form. You can see a reproduction of this by pasting the below code into the docs here

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [x] I have run eslint on the code
• [ ] I have added JSDoc for all of my code (where applicable)
• [ ] I have added tests to cover my changes.

Priority:

• [x] Normal
• [ ] High

Related Issues:

Fixes #150