[py] add doc for driver_path_env_key

[Delta456]

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Description

Adds doc for driver_path_env_key as they were missing

Motivation and Context

Makes the doc easier to know and use the parameter

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

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PR Type

Documentation, Enhancement

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Description

• Added documentation for the driver_path_env_key parameter across all major browser service classes (Chromium, Edge, Firefox, Safari)
• The parameter allows users to specify an environment variable that contains the path to the driver executable
• Improves code documentation and makes the parameter usage more clear for developers

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Changes walkthrough 📝

Relevant files

Documentation

service.py Add driver_path_env_key documentation to ChromiumService  py/selenium/webdriver/chromium/service.py Added documentation for driver_path_env_key parameter in ChromiumService class +1/-0      service.py Add driver_path_env_key documentation to Edge Service        py/selenium/webdriver/edge/service.py Added documentation for driver_path_env_key parameter in Edge Service class +1/-0      service.py Add driver_path_env_key documentation to Firefox Service  py/selenium/webdriver/firefox/service.py Added documentation for driver_path_env_key parameter in Firefox Service class +1/-0      service.py Add driver_path_env_key documentation to Safari Service    py/selenium/webdriver/safari/service.py Added documentation for driver_path_env_key parameter in Safari Service class +1/-0

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[qodo-merge-pro]

PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

⏱️ Estimated effort to review: 1 🔵⚪⚪⚪⚪

🧪 No relevant tests

🔒 No security concerns identified

⚡ No major issues detected

[qodo-merge-pro]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Score
General	Clarify documentation to indicate platform-specific behavior of a parameter Add a note that the driver_path_env_key parameter may be ignored on macOS since Safari's driver location is typically fixed at /usr/bin/safaridriver py/selenium/webdriver/safari/service.py [35] -:param driver_path_env_key: (Optional) Environment variable to use to get the path to the driver executable. +:param driver_path_env_key: (Optional) Environment variable to use to get the path to the driver executable. Note: On macOS, Safari's driver is typically fixed at `/usr/bin/safaridriver`. Apply this suggestion Suggestion importance[1-10]: 5 Why: The suggestion adds valuable platform-specific context about Safari's driver location on macOS, which helps users understand potential limitations of the parameter. However, it's only a documentation improvement with moderate impact.	5