docs: Add example on how to set entrypoint for a plugin using `pyproject.toml`

[Aviksaikat]

Overview

Provide a simple overview of what you wish to see added. Please include:

• docs: Add example on how to set entry point for a plugin using pyproject.toml

Specification

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Dependencies

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[linear]

APE-1789 docs: Add example on how to set entrypoint for a plugin using `pyproject.toml`