Fix for trailing backslash validation issue.

[Joshua-Donovan]

#475

Add trim delete to file path, removing trailing \ when present.

• Tests Ran:
  • file name including appended '\' Result: the trailing backslash is removed
  • file name not including '\' Result: no changes made to file path
  • file name actually includes a trailing '\' (actually part of the file name) Result: the check will fail with an invalid file path error.