Spring-ai Ollama integration tests fix

• Disable tests by default
• Improve Testcontainers configuration

Comment From: tzolov

this helps :)

Comment From: ThomasVitale

@tzolov yeah, sorry, after testing the rebase I forgot to switch that off again. The Testcontainers-based Ollama tests should run ok as part of the GitHub Actions workflow, so we could remove the disabling logic. The error that happened was actually because the tests were running on native Ollama.