Adds default team to the remote cluster entity (#27863)

* Adds default team to the remote cluster entity

A new DefaultTeamId field is added to the RemoteCluster entity and its
endpoints, and used when receiving channel invites to choose in which
team to create a new channel.

This will be later extended with the ability for the system admin to
manually accept invites, choosing which team to create the channel on
each. This use case will be triggered when the DefaultTeamId field is
empty, which now simply chooses the first team it finds in the
database as a fallback.

* Fix migrations list

* Fixes channelinvite test case

* Fix i18n

* Fix migration list

server/public/model/remote_cluster_test.go

@@ -27,6 +27,8 @@ func TestRemoteClusterIsValid(t *testing.T) {
 		{name: "Missing create_at", rc: &RemoteCluster{RemoteId: id, Name: NewId(), SiteURL: "example.com"}, valid: false},
 		{name: "Missing last_ping_at", rc: &RemoteCluster{RemoteId: id, Name: NewId(), SiteURL: "example.com", CreatorId: creator, CreateAt: now}, valid: true},
 		{name: "Missing creator", rc: &RemoteCluster{RemoteId: id, Name: NewId(), SiteURL: "example.com", CreateAt: now, LastPingAt: now}, valid: false},
+		{name: "Bad default_team_id", rc: &RemoteCluster{RemoteId: id, Name: NewId(), SiteURL: "example.com", CreateAt: now, LastPingAt: now, CreatorId: creator, DefaultTeamId: "bad-id"}, valid: false},
+		{name: "Valid default_team_id", rc: &RemoteCluster{RemoteId: id, Name: NewId(), SiteURL: "example.com", CreateAt: now, LastPingAt: now, CreatorId: creator, DefaultTeamId: NewId()}, valid: true},
 		{name: "RemoteCluster valid", rc: &RemoteCluster{RemoteId: id, Name: NewId(), SiteURL: "example.com", CreateAt: now, LastPingAt: now, CreatorId: creator}, valid: true},
 		{name: "Include protocol", rc: &RemoteCluster{RemoteId: id, Name: NewId(), SiteURL: "http://example.com", CreateAt: now, LastPingAt: now, CreatorId: creator}, valid: true},
 		{name: "Include protocol & port", rc: &RemoteCluster{RemoteId: id, Name: NewId(), SiteURL: "http://example.com:8065", CreateAt: now, LastPingAt: now, CreatorId: creator}, valid: true},