Added comments about Llama3 weights to Llama tutorial

[pggPL]

Description

Meta released LLama 3 model in April. We have tutorial for Llama 2. It turned out that it works with Llama 3. I changed comments within tutorial. They inform that the code can be run with Llama 3 weights as well. I did not change the benchmark time(it's only Llama 2).

Type of change

• [x] Documentation change (change only to the documentation, either a fix or a new content)
• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)

Changes

Please list the changes introduced in this PR:

• changes in comments and markdown part in the Llama tutorial,

Checklist:

• [x] I have read and followed the contributing guidelines
• [x] The functionality is complete
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [ ] I have added tests that prove my fix is effective or that my feature works
• [x] New and existing unit tests pass locally with my changes