[Doc]Update flex flow doc

[D-W-]

Description

Please add an informative description that covers that changes made by the pull request and link all relevant issues. This pull request includes changes to the docs/how-to-guides/develop-a-flex-flow directory, specifically the class-based-flow.md and function-based-flow.md files. The changes primarily involve the addition of new configurations and parameters to the examples provided in these files.

• docs/how-to-guides/develop-a-flex-flow/class-based-flow.md: Added AzureOpenAIModelConfiguration to the example and updated the pf.run method to include the model_config and flow_config parameters. This provides a more detailed example of how to run a flow class directly with specific configurations.
• docs/how-to-guides/develop-a-flex-flow/function-based-flow.md: Added inputs to the sample section of the flow YAML example. This shows how to specify inputs in a flow YAML file.

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• [ ] The pull request does not introduce [breaking changes].
• [ ] CHANGELOG is updated for new features, bug fixes or other significant changes.
• [ ] I have read the contribution guidelines.
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• [ ] There are a small number of commits, each of which have an informative message. This means that previously merged commits do not appear in the history of the PR. For more information on cleaning up the commits in your PR, see this page.

Testing Guidelines

• [ ] Pull request includes test coverage for the included changes.