test: address failing tests

[ajbozarth]

Description

While working on #397 I was updating some tests and when I ran pytest some tests were failing. I found that our CI only runs pytest -m unit which is a small subset of our total tests. I opened #400 to handle adding the correct decorators to all our tests, but addressed the failing tests here.

Changes:

• fixed errors_test.py which were failing since feat: retryable implementation #363 was merged
• renamed workflows/multi_agents.py to workflows/test_multi_agents.py since pytest only looks for files named test_*.py or *_test.py, once run these tests were failing due to an invalid ollama model.
• I updated the default ollama model to be llama3.1 instead of llama3.1:8b. I have llama3.1:latest installed locally and not llama3.1:8b so this e2e test was erroring. By updating the default to remove the tag it addresses the issue and matches will all other use cases in the current code.

Checklist

• I have read the contributor guide
• I have signed off on my commit
• Tests are included
• Documentation is changed or added
• Commit messages and PR title follow conventional commits