fix: test ut_lind_fs_read_from_directory

[ChinmayShringi]

Description

Fixes # (issue)

Added a clean-up step to ensure the test environment is always reset before the mkdir operation in the ut_lind_fs_read_from_directory test case. The line let _ = cage.rmdir_syscall(old_path); was introduced to remove the directory if it already exists, ensuring a clean environment for testing. This change enhances the reliability of the test by preventing conflicts from pre-existing directories.

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

• cargo test ut_lind_fs_read_from_directory

Checklist:

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• Any dependent changes have been added to a pull request and/or merged in other modules (native-client, lind-glibc, lind-project)