revert: esptool 5 requirements. will do it in pytest-embedded 2.x

[hfudev]

No description provided.

[Copilot]

Pull Request Overview

This PR reverts changes related to esptool version 5 requirements, postponing this upgrade to pytest-embedded 2.x. The changes simplify dependency management by removing Python version-specific esptool requirements and fix a parameter formatting issue.

• Reverts esptool dependency to a single version constraint (~=4.9) instead of Python version-specific requirements
• Fixes argument formatting in the flash function by removing underscore-to-hyphen replacement

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
pytest-embedded-serial-esp/pyproject.toml	Simplifies esptool dependency from version-specific constraints to single ~=4.9 requirement
pytest-embedded-idf/pytest_embedded_idf/serial.py	Removes underscore-to-hyphen replacement in argument formatting for flash function

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