Use config list in notebook

[sonichi]

Why are these changes needed?

• Use config list in a notebook to pass test.
• Fix error in llm_configuration notebook.
• Use the right config list for a few notebooks.

Related issue number

#2490

Checks

• I've included any doc changes needed for https://microsoft.github.io/autogen/. See https://microsoft.github.io/autogen/docs/Contribute#documentation to build and test documentation locally.
• I've added tests (if relevant) corresponding to the changes introduced in this PR.
• I've made sure all auto checks have passed.