Update max_length to max_new_tokens in Chapter 1 3.mdx

[Diyasingh03]

docs: Update text generation examples to use max_new_tokens

Replace max_length with max_new_tokens in the pipeline("text-generation", ...) example within the LLM course documentation. This aligns with recommended best practices for controlling the generated output length and provides a clearer demonstration for users.

generator(
"In this course, we will teach you how to",
max_new_tokens=30, # Use max_new_tokens here
num_return_sequences=2,
)

[HuggingFaceDocBuilderDev]

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