.Net: Extend function calling model to support strict mode

[SergeyMenshykh]

Context: {Azure}OpenAI support the 'strict' mode for function calling that tells the model to adhere to JSON schema of the function definition:

Source: https://platform.openai.com/docs/guides/function-calling

Enabling this mode should ensure that the arguments generated by the model for a function call exactly match the JSON Schema provided in the function definition.

ToDo: Add the new AllowStrictSchemaAdherence property to the FunctionChoiceBehaviorOptions class allowing activation of the strict mode for function calling.