Fix syntax error in Ollama example code

[lazzyms]

Fixes: #110
Problem
The Ollama example code in README.md contains a syntax error (missing comma) that prevents users from running the example successfully. When users copy the example code, they encounter the error: "API key must be provided for cloud-hosted models via the api_key parameter or the LANGEXTRACT_API_KEY environment variable."
Solution
Added the missing comma after the language_model_type=inference.OllamaLanguageModel parameter in the Ollama integration example.
Changes

File modified: README.md
Change: Added missing comma in Ollama example code after language_model_type parameter
Impact: Users can now copy and run the Ollama example without syntax errors

Testing

Verified the corrected syntax is valid Python code
Confirmed parameter formatting is consistent with other examples in the README
Validated the example runs without the previous API key error

Type of Change

Bug fix (non-breaking change which fixes an issue)
Documentation update
New feature
Breaking change

This is a simple documentation fix that resolves a syntax error preventing users from following the Ollama integration guide.

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