[MM-27535] User invite limits for MM Cloud (#15197)

* Add a config for MM User Limit

* Adding graceful errors for if an administrator invites people passed their user limit

* Including changed vendor files

* Adding unit test

* Fix a bug

* Push up working tests (Thanks Joram)

* Add more cases, clean up logs in code

* One more case

* Refactoring based on PR comments

* Updating i18n

* Some changes based on PR review

* Remove a comment

* Bring back some translations that were somehow removed

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

app/app_iface.go

@@ -537,6 +537,7 @@ type AppIface interface {
 	GetEmojiByName(emojiName string) (*model.Emoji, *model.AppError)
 	GetEmojiImage(emojiId string) ([]byte, string, *model.AppError)
 	GetEmojiList(page, perPage int, sort string) ([]*model.Emoji, *model.AppError)
+	GetErrorListForEmailsOverLimit(emailList []string, cloudUserLimit int64) ([]string, []*model.EmailInviteWithError, *model.AppError)
 	GetFile(fileId string) ([]byte, *model.AppError)
 	GetFileInfo(fileId string) (*model.FileInfo, *model.AppError)
 	GetFileInfos(page, perPage int, opt *model.GetFileInfosOptions) ([]*model.FileInfo, *model.AppError)