Remove or handle warnings raised by test functions

[janbridley]

Description

Several deprecation warnings are raised by previous tests calling old methods, so the tests have been updated to call the new variants. A minimum setter value was defined for polyhedra to avoid setting volumes and areas to subnormal values. This parameter was left at 2e-16, which is more than small enough for basically all use cases. polygon_test now uses rowan to generate random quaternions, eliminating errors that arose from the previous generation method.

Types of Changes

• Documentation update
• Test update
• Bug fix
• New feature
• Breaking change¹

¹The change breaks (or has the potential to break) existing functionality.

Checklist:

• I am familiar with the Contributing Guidelines.
• I agree with the terms of the Contributor Agreement.
• The changes introduced by this pull request are covered by existing or newly introduced tests.
• I have updated the changelog and the credits.