fix: allow refund_policy to be none

[snitin315]

for fossasia/open-event-frontend#5036

[snitin315]

we need a migration for past events, right?

[codecov]

Codecov Report

Merging #7254 into development will not change coverage.
The diff coverage is 100.00%.

@@             Coverage Diff              @@
##           development    #7254   +/-   ##
============================================
  Coverage        63.55%   63.55%           
============================================
  Files              259      259           
  Lines            13034    13034           
============================================
  Hits              8284     8284           
  Misses            4750     4750           

Impacted Files	Coverage Δ
app/api/schema/events.py	96.89% <100.00%> (ø)
app/models/event.py	77.47% <100.00%> (ø)

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[iamareebjamal]

Yes, we need to set refund policy to null for previous events.

[iamareebjamal]

Thinking about it now, if some user changed their refund policy using the API, making it null will lead to data loss. So, wait for Mario to tell what should be done

[snitin315]

Thinking about it now, if some user changed their refund policy using the API, making it null will lead to data loss. So, wait for Mario to tell what should be done

I think we can apply migration only to events having the default refund_policy message.

[mariobehling]

In regards to events we should delete the policy. There was not any organizer who edited the policy, we just introduced it a few hours ago.

Is that easy to do? I dont think we need migrations.

[iamareebjamal]

We didn't add it a few hours ago. We used it as default refund policy for all events in the backend since a long time ago

[lgtm-com]

This pull request introduces 2 alerts when merging bd63158 into 97f3497 - view on LGTM.com

new alerts:

• 2 for Unused import