Enable cmake color output for clang/ninja

[janbridley]

As in ninja-build/Ninja's FAQ, cmake does not color output for build systems that buffer output. The code added in this PR fixes this

How Has This Been Tested?

CMake colors output with the changes made, and does not without.

Before:

After:

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds or improves functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation improvement (updates to user guides, docstrings, or developer docs)

Checklist:

• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• I have updated the documentation (if relevant).
• I have added tests that cover my changes (if relevant).
• All new and existing tests passed.
• I have updated the credits.
• I have updated the Changelog.