If live gutter is turned on, it will run "diff" after every command

[geza-herman]

If live gutter is turned on (git-gutter:update-interval is non-nil), git-gutter will run diff after every keystroke, no matter whether it actually modified the buffer or not. Just moving the cursor causes a diff call. I believe https://github.com/emacsorphanage/git-gutter/pull/204 introduced this behavior.