Reduce logo sizes even more (helix-editor#9211)

* Reduce logo.svg even more

While reading through commits to helix I saw
helix-editor#9106 and wondered if the
relatively-new-to-me svgo would do better than -95B diff, indeed it
does. Seeing as this file is "a minified file we're basically treating
as binary" anyway I figured might as well minify it further.

* Minimize all the svg logos