chore(deps): update ollama requirement

Updates the requirements on [ollama](https://github.com/ollama/ollama-python) to permit the latest version.

Updates `ollama` to 0.4.2
- [Release notes](https://github.com/ollama/ollama-python/releases)
- [Commits](ollama/ollama-python@v0.3.3...v0.4.2)

---
updated-dependencies:
- dependency-name: ollama
  dependency-type: direct:production
  dependency-group: dependencies
...

Signed-off-by: dependabot[bot] <support@github.com>

projects/pgai/pyproject.toml

@@ -15,7 +15,7 @@ dependencies = [
     "langchain-openai>=0.1,<1.0",
     "langchain-text-splitters>=0.2,<1.0",
     "pydantic>=2.0,<3.0",
-    "ollama>=0.3.3,<0.4.0",
+    "ollama>=0.3.3,<0.5.0",
     "openai>=1.44,<2.0",
     "python-dotenv>=1.0,<2.0",
     "structlog>=24.0,<25.0",