Add basic export to the AEFI directory

[obinna-h-n]

Feature Description

Permit users to export data from the AEFI directory. This is part of the epic (#12634) on AEFI module.

Added Value/Benefit

Instead of having to run SQL queries on the database, users can export data on adverse events following immunization in a user friendly way

Acceptance Criteria

• [ ] In the AEFI directory, a new "Export" button has been introduced, that does a basic .csv export of AEFI data. It is located in the top right section of the header to the right of the Import button and is only accessible by users who possess the AEFI_EXPORT user right.