Vim has an area off to the left where it can display information for specific lines in a buffer. This is sometimes called the gutter or the tray. In the Vim help files it is called the signcolumn. That names makes sense. It is a column to the left of the line numbers where signs can be shown to indicate git status, type errors, and lint warnings.

By default, the signcolumn is set to auto which means that as a sign appears, the column shifts open moving the editor text with it. When you've resolved whatever cause the sign to disappear, everything will shift back to the left.

This jumpy layout shift can be avoiding by keeping the signcolumn always open. That's done by setting it to yes in your ~/.vimrc.

set signcolumn=yes

See :h signcolumn for more details.