As long as you comply with the Community Guidelines https://www.twitch.tv/p/legal/community-guidelines/ and the Developer Agreement https://www.twitch.tv/p/legal/developer-agreement/ then you’re allowed to run a bot.
If you’re testing your bot in another streams channel without their permission though, sending messages to chat you may be considered a spam bot and violate the community guidelines. If you have permission from the broadcaster to use your bot in their channel then there shouldn’t be any issue as long as you follow the guidelines/legal agreements I linked.