add source_urls and code_url

[nerdai]

Description

Added kwargs to run() of LlamaDatasetMetadataPack:

• source_urls
• code_url

Fixes # (issue)

Type of Change

Please delete options that are not relevant.

• [x] Bug fix / Smaller change

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• [x] I stared at the code and made sure it makes sense