Allow joining public clans w/o invite token

[bukajsytlos]

No description provided.

[Brutus5000]

Looks good. Needs adjustment and co-release on the website before merging.

[codecov]

Codecov Report

❌ Patch coverage is 89.58333% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 77.15%. Comparing base (6c6f388) to head (ca8e310).
⚠️ Report is 171 commits behind head on develop.

Files with missing lines	Patch %	Lines
...n/java/com/faforever/api/clan/ClansController.java	50.00%	2 Missing ⚠️
...rever/api/data/listeners/ClanEnricherListener.java	75.00%	0 Missing and 1 partial ⚠️
...n/java/com/faforever/api/player/PlayerService.java	75.00%	1 Missing ⚠️
...ava/com/faforever/api/voting/VotingController.java	50.00%	1 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##             develop     #428      +/-   ##
=============================================
+ Coverage      77.00%   77.15%   +0.14%     
- Complexity      1225     1231       +6     
=============================================
  Files            249      249              
  Lines           3806     3844      +38     
  Branches         241      243       +2     
=============================================
+ Hits            2931     2966      +35     
- Misses           775      778       +3     
  Partials         100      100              

Files with missing lines	Coverage Δ
.../main/java/com/faforever/api/clan/ClanService.java	100.00% <100.00%> (ø)
...IgnoreOctetStreamToObjectHttpMessageConverter.java	28.57% <ø> (ø)
...api/config/NoopMultipartFileToStringConverter.java	66.66% <ø> (ø)
.../main/java/com/faforever/api/data/domain/Clan.java	100.00% <100.00%> (ø)
...c/main/java/com/faforever/api/error/ErrorCode.java	99.15% <100.00%> (+<0.01%)	⬆️
...ain/java/com/faforever/api/map/MapsController.java	68.18% <100.00%> (ø)
...ain/java/com/faforever/api/mod/ModsController.java	75.00% <100.00%> (ø)
...rever/api/data/listeners/ClanEnricherListener.java	88.88% <75.00%> (-11.12%)	⬇️
...n/java/com/faforever/api/player/PlayerService.java	71.42% <75.00%> (+4.76%)	⬆️
...ava/com/faforever/api/voting/VotingController.java	9.09% <50.00%> (ø)
... and 1 more

... and 1 file with indirect coverage changes

---

Continue to review full report in Codecov by Sentry.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 6c6f388...ca8e310. Read the comment docs.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.