[SOLVED]: Yarn Debian Key Expiry Date Updated

 Solved by re-installing:

 curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -  
 echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list  
 sudo apt update  
 sudo apt install yarn  

Ref: https://linuxize.com/post/how-to-install-yarn-on-ubuntu-20-04/