removed the .ics attachment for partner registration confirmation emails

[jerryxu99]

🎟️ Ticket(s): Closes # INTERIM soln for https://www.notion.so/ubcbiztech/b24732925a6745caa305a2c746fa5ba7?v=d557178d0a134acf85a3890882538364&p=b43039995bec41b3b3e7f4eeae26acd2&pm=s

👷 Changes: A brief summary of what changes were introduced. Removes the .ics from the partner reg confirmation email.

The long term goal for this ticket still remains in that partners should only be sent a singular email, rather than two emails.

PICTURE: Shows that there is no .ics attachment for partner registrations

💭 Notes: Any additional things to take into consideration.

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