Update docker image - vimflowy/vimflowy - to latest version

[joboyx]

Hi WTJeff, first off love your work man! Keep it up.

Since I'm hitting the 5MB max local storage of the browser, I'm now looking at running vimflowy server via docker locally.

However I noticed that last build was from 2 years ago (May 6, 2020).

https://hub.docker.com/r/vimflowy/vimflowy/tags

And I saw that there were recent commits in 2021.

Can you update the image in docker hub with latest version same as web (wuthejeff.com/vimflowy/)?

Thanks.