Improve RC workflow: Enhanced validation and error handling in Makefile

What?

Improved the bump-test-version target in the Makefile to ensure proper validation of the provided release candidate (RC) versions.
Added logic to fetch the latest version and the latest RC version from PyPI.
Implemented checks to validate that the provided RC version is either starting from rc0 if no RC versions exist or incrementing the latest RC version from PyPI.
Enhanced error handling and messaging to provide clearer feedback during the version bump process.

To ensure that version increments are consistent and follow the existing versioning scheme on PyPI.
To prevent invalid RC versions from being set, which could lead to confusion and potential issues during the release process.
To automate the version bump process with proper validation, reducing manual errors and improving the release workflow.
To provide clear and informative messages to developers when using the Makefile, improving the overall development experience.

Refer to the Makefile best practices for additional context on the changes made.

Review the checklist here