[py] used pathlib module to check if the file exist in remote/file_detector.py

[sandeepsuryaprasad]

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Description

Currently we are using os module to check if the file exist's in local machine in function is_local_file. I have just optimised the current logic using pathlib module which uses OO approach.

Motivation and Context

• The logic to check if the file exists on local disk is bit lengthy using os module, which we are currently doing in is_local_file function in remote/file_detector.py module.

• I have just optimised the logic using pathlib module which takes just one line of code.

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.

[diemol]

Thank you!