partial fix for delete_invite error DDS-1264

[valyo]

Fixes DDS-1264 partially; we need to make sure that we avoid invites with strange created_at date, and to handle informing the user, perhaps.

• Tests passing
• Black formatting
• Rebase/merge the dev branch
• Note in the CHANGELOG

[codecov]

Codecov Report

Merging #1163 (bb4ec6a) into dev (7540974) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##              dev    #1163      +/-   ##
==========================================
+ Coverage   84.04%   84.05%   +0.01%     
==========================================
  Files          29       29              
  Lines        3447     3450       +3     
==========================================
+ Hits         2897     2900       +3     
  Misses        550      550              

Impacted Files	Coverage Δ
dds_web/scheduled_tasks.py	71.55% <100.00%> (+0.75%)	⬆️

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[i-oden]

@valyo Could you add a little note in the PR description on why it's temporary?

[i-oden]

Small suggestion. Everything looks good though and it works.
Let me know if you commit the suggestion or if you want to keep it as it is now.

[i-oden]

Btw, could we add a test for this in test_scheduled_tasks.py?

[i-oden]

Add a test for this (as we discussed) when you have the chance

[i-oden]

Looks good!