Refactor frame method to use isEmpty for list check and String check.

[manuelsblanco]

• Replace frameElements.size() == 0 with frameElements.isEmpty() in the frame method of RemoteWebDriver.

This change improves code readability and adheres to best practices for checking if a list is empty.

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Description

Refactor in RemoteWebDriver:
Updated the frame method to use isEmpty() instead of size() == 0 for checking if a list is empty.
Refactor in Platform Initialization:
Replaced "".equals(platformString) with platformString.isEmpty() for checking if a string is empty during the platform initialization.

Motivation and Context

The primary motivation behind these changes is to improve the code quality by enhancing readability and adhering to Java's best practices. The existing code, while functional, had areas where readability and maintainability could be improved.

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.

[titusfortner]

Thank you.