E: The repository ‘http://ppa.launchpad.net/webupd8team/sublime-text-3/ubuntu bionic Release’ does not have a Release file.
N: Updating from such a repository can’t be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
Background: Under Ubuntu18.04.2, I wanted to reinstall sublime, and manually deleted all sublime configuration files
Purpose: I wanted to completely reinstall sublime text3
Problem: There was a problem when sudo apt-get update updated the software source
Solution: Enter cd /etc/apt/sources.list.d to delete the source about sublime
