Why would you want to shoot yourself? Don’t do x.

Be careful that people don’t think you’re contractually agreeing to something with the emoji: https://www.theguardian.com/world/2023/jul/06/canada-judge-thumbs-up-emoji-sign-contract

Let’s Encrypt supports DNS verification, if you have access to update the zone file. It makes automation harder, but there are scripts to do the DNS update for the verification.