Smaller button image for use in lists

[grayside]

Lists of deployable apps look better with a smaller button, but to resize the image on GitHub requires leaving markdown for HTML. Add a smaller image that can be referenced to keep it simple.

This is what I'm currently experimenting with:

<img src="https://storage.googleapis.com/cloudrun/button.svg" alt="Run on Google Cloud" height="20">

[ahmetb]

I am thinking we should probably scale down the original svg so that people don’t resort to html.

[grayside]

Agreed, better to have button-small.svg

[ahmetb]

I tried height=40 (by saving this to github gists + save as .md), and it seems to render better. height=20 is a bit too small.

Currently it's 50px, so shrink by 20% would be good enough.