Fixes #15 Add unit tests for addFileExclude Method

[ShirshenduR]

Description

Summary of the change:

• Added unit tests for the addFileExclude method to ensure it correctly adds file names to the exclusion list and prevents duplicates.

• Fixes Write Unit Tests for addFileExclude Method #15

Type of change

Please delete options that are not relevant.

• [x ] Tests update

Checklist

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

Screenshots (if applicable)

[ShirshenduR]

@Kota-Karthik @techy4shri Please review

[Kota-Karthik]

@ShirshenduR LGTM!
Thank you!