Update searcharr.py

[Jorman]

Added the chat_id tag so now the tag will be:
searchatt-usernameORuserid-chatID

[toddrob99]

Thanks for the contribution. This needs to be configurable, because there is a common use case where appending the chat id will result in duplicate tags for a given user. I sometimes invoke my bot through a direct message, and other times in a group chat. I don't want two tags for myself based on which chat I use the bot in.

Please add a setting and make it default to the current production functionality.