[MM-61097] Fix errcheck issues in server/channels/app/bot.go (#28785)

Co-authored-by: Ben Schumacher <ben.schumacher@mattermost.com>

server/.golangci.yml

@@ -88,7 +88,7 @@ issues:
         channels/app/app_test.go|\
         channels/app/authorization_test.go|\
         channels/app/auto_responder_test.go|\
-        channels/app/bot.go|\
+        channels/app/bot_test.go|\
         channels/app/brand.go|\
         channels/app/busy_test.go|\
         channels/app/channel.go|\