Update Irradiance Pipeline for test and dataset generation

[jacobbieker]

Pull Request

Description

This updates the irradiance pipeline to exclude from training around 100 sites, and provides getting information about the site ID and initialization time for generating the test/inference dataset.

Fixes #

How Has This Been Tested?

Training with it

Checklist:

• [ ] My code follows OCF's coding style guidelines
• [ ] I have performed a self-review of my own code
• [ ] I have made corresponding changes to the documentation
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] I have checked my code and corrected any misspellings