[MM-39299] Remove outdated translations and update go-i18n library (#18674)

* Remove outdated translations

* update go-i18n dependency

* reflect review comments

* add message count for languages which has two translations for plurals

vendor/github.com/mattermost/go-i18n/i18n/bundle/bundle.go

@@ -386,12 +386,13 @@ func (b *Bundle) translate(lang *language.Language, translationID string, args .
 		countInt, ok := count.(int)
 		if ok && countInt > 1 {
 			template = translation.Template(language.Other)
-			if template == nil {
-				return translationID
-			}
 		}
 	}
 
+	if template == nil {
+		return translationID
+	}
+
 	s := template.Execute(data)
 	if s == "" {
 		return translationID

vendor/modules.txt

@@ -374,7 +374,7 @@ github.com/mailru/easyjson
 github.com/mailru/easyjson/buffer
 github.com/mailru/easyjson/jlexer
 github.com/mailru/easyjson/jwriter
-# github.com/mattermost/go-i18n v1.11.0
+# github.com/mattermost/go-i18n v1.11.1-0.20211013152124-5c415071e404
 ## explicit
 github.com/mattermost/go-i18n/i18n
 github.com/mattermost/go-i18n/i18n/bundle