Stop using media_slugs verbatim

[aleksfl]

Scope and purpose

Fixes #1923.
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[github-actions]

Test results

    8 files  1 744 suites   3m 12s ⏱️
  943 tests   942 ✅ 1 💤 0 ❌
7 544 runs  7 536 ✅ 8 💤 0 ❌

Results for commit c44d281.

♻️ This comment has been updated with latest results.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.61%. Comparing base (19fa02e) to head (c44d281).
⚠️ Report is 8 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1953      +/-   ##
==========================================
+ Coverage   88.52%   88.61%   +0.08%     
==========================================
  Files         148      148              
  Lines        7135     7173      +38     
==========================================
+ Hits         6316     6356      +40     
+ Misses        819      817       -2     

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[hmpf]

There is such a thing as too much consistency.

I'm thinking we should instead have a constant "EMAIL_DESTINATION_SLUG", as nothing not in the tree below argus.notificationprofile.media should be imported out. But where to put it? It could be on argus.notificationprofile.media, it could be on argus.notificationprofile too maybe.

None of the other media types are special cased like this.

Another possibility is moving the signal and only attaching it if the email plugin is in use but that's a lot more work and takes more thinking.

[hmpf]

It is more okay with the v2 API since that is deprecated anyway.

[aleksfl]

I added the constant to media since that seemed most natural. It's not ideal but it works.

[hmpf]

See the comment on signals. I could have said the same here but this serializer is after all deprecated so when it is deleted all sins will be forgotten =)

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud