Handle Missing File Uploads in /submit Route (app.py)

[DevROHIT11]

Description:
The filename variable is only defined if a file is uploaded, which can lead to an UnboundLocalError when the add_registration procedure is called without an uploaded file.

Suggested Fix:

1. Initialize filename to None at the start of the file upload logic.
2. Update the stored procedure to handle NULL values for filename or provide a default value.

[github-actions]

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