Increase test coverage

[c-w]

No description provided.

[codecov-io]

Codecov Report

Merging #235 into master will increase coverage by 1.74%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #235      +/-   ##
==========================================
+ Coverage   96.78%   98.53%   +1.74%     
==========================================
  Files          20       14       -6     
  Lines         996      955      -41     
==========================================
- Hits          964      941      -23     
+ Misses         32       14      -18

Impacted Files	Coverage Δ
opwen_email_server/utils/email_parser.py	94.96% <100%> (+0.88%)	⬆️
opwen_email_server/utils/log.py	100% <100%> (+2.53%)	⬆️
opwen_email_server/services/storage.py	96.96% <100%> (+0.45%)	⬆️
opwen_email_server/actions.py	100% <100%> (+3.24%)	⬆️
opwen_email_server/utils/unique.py	100% <100%> (ø)
opwen_email_server/constants/cache.py
opwen_email_server/constants/sync.py
opwen_email_server/constants/queues.py
opwen_email_server/constants/events.py
opwen_email_server/constants/sendgrid.py
... and 8 more

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