[feature] default delimiter for CSVs

[shpiyu]

Description

To make ingen config less verbose I am removing the required delimiter config. If this config param is not present comma will be used as the default delimiter for CSV files.

Changes Made

• Use comma as default parameter
• This PR also adds the missing openpyxl requirement of FileReader

Definition of Done

Before submitting this pull request, please ensure that the following criteria have been met:

• All automated tests have passed successfully.
• All manual tests have passed successfully.
• Code has been reviewed by at least one other team member.
• Code has been properly documented and commented as needed.
• All new and existing code adheres to our project's coding standards.
• All dependencies have been added or removed from the project's README or other documentation as needed.
• Any relevant documentation or help files have been updated to reflect the changes made in this pull request.
• Any necessary database migrations have been run.
• Any relevant UI changes have been reviewed and approved by the UI/UX team.