added test_fileMetadata.py

[Sai-ganesh-0004]

Description
This PR introduces the file test_fileMetadata.py, which contains unit tests for the insert_file method in the FileMetadata class. These tests ensure that:

• A new file path can be successfully inserted into the metadata.
• Duplicate file paths are not added to the list

Fixes #7: Added unit tests for the insert_file method in the FileMetadata class to ensure that new files can be added correctly and that duplicates are not inserted.

Type of change

• Tests update

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• New and existing unit tests pass locally with my changes
• I have maintained a clean commit history by using the necessary Git commands
• I have checked that my code does not cause any merge conflicts

So what I have done is I have created 4 dummy files to test the behavior of the insert_file method and tested based on that.

[Kota-Karthik]

@Sai-ganesh-0004
delete this file twinTrim/dataStructures/test_fileMetadata.py

[Sai-ganesh-0004]

Can you check it once

[techy4shri]

@Sai-ganesh-0004 We will check this as soon as we can!

[Kota-Karthik]

@Sai-ganesh-0004 LGTM!