Improve EPP login

[artur-intech]

@ratM1n or @teadur Notice new setting https://github.com/internetee/registry/pull/1314/files#diff-fc5026eef1f4752ef71315b36727e708R161

Fixes #1313, #587.

[vohmar]

#587 test failed - user is able to log in unlimited number of times. Cannot find how to set the session limit (#543) - unable to test nor verify

[artur-intech]

#587 test failed - user is able to log in unlimited number of times. Cannot find how to set the session limit (#543) - unable to test nor verify

Well, then it either means session limit per registrar never worked or there is something wrong with EPP proxy integration, since this PR only changes response code and does not touch any logic. I will check.

[artur-intech]

I need detailed description of how you test it.

[artur-intech]

#729

[vohmar]

#1313 is ok, second attempt to login in already auhtenitaed session resulted in error 2002 as expected.
#587 is still an issue - set the auth limit on application.yml to 4, sessions db table is clear, but user is still able to create more than 4 parallel sessions - in our test example 7 active sessions were created. To test, user form the same ip opens up multiple sessions directly to the epp interface (epptelnet)

[artur-intech]

See my previous comment.

[artur-intech]

#1331 should help.

[vohmar]

blocked by #1331

[yulgolem]

@ratM1n let's check this branch on staging.
Locally 5th login attempt with non-expired sessions goes 2502:Session limit exceeded; server closing connection (connection limit reached).

[ratM1n]

Did I miss something, but after adding epp_sessions_per_registrar: '4' to application.yml and restart, I'm getting on login:

<result code="2502"> <msg lang="en">Session limit exceeded; server closing connection (connection limit reached)</msg> </result>

[ratM1n]

OK! seems to work correctly and also ignore expired sessions if present in database.