Limit party size to 30 members (#8589)

* Added a field in Party page with members count and maximum members in party

* Added information of invitations counter

* Limited party to 2 members on server (API)

* Fixed english text

* Consider current number of invitations in the party

* Moved PARTY_LIMIT_MEMBERS to common folder

* Access the PARTY_LIMIT_MEMBERS through groupsCtrl

* Some corrections

* Hide invite button when invite limit is reached

* Added missing trailing comma

* Do not test 'returns only first 30 invites' in a party anymore, but in a guild: party is limited to 30 members, so it would always fail

* Test: allow 30 members in a party

* Test: do not allow 30+ members in a party

* Improved 'allow 30 members in a party' test

* Test: 'allow 30+ members in a guild'

* Added missing trailing comma

* Code style corrections

* Fixed new line position

* Party limit check done inside Group.validateInvitations function

* Improved members count query

* Fixed tests

* Rewrite tests

* Removed import of BadRequest: value became unused

* Added 'await' to remaining 'Group.validateInvitations' functions

* Fixed tests that would always success

website/common/script/index.js

@@ -27,6 +27,7 @@ import {
   LARGE_GROUP_COUNT_MESSAGE_CUTOFF,
   SUPPORTED_SOCIAL_NETWORKS,
   GUILDS_PER_PAGE,
+  PARTY_LIMIT_MEMBERS,
 } from './constants';
 
 api.constants = {
@@ -34,6 +35,7 @@ api.constants = {
   LARGE_GROUP_COUNT_MESSAGE_CUTOFF,
   SUPPORTED_SOCIAL_NETWORKS,
   GUILDS_PER_PAGE,
+  PARTY_LIMIT_MEMBERS,
 };
 // TODO Move these under api.constants
 api.maxLevel = MAX_LEVEL;