internal(readme): update readme

README.md

@@ -1,5 +1,5 @@
 <p align="center">
-  <img src="./assets/visx-header.png" />
+  <img src="./assets/visx-geometry.png" />
 </p>
 
 <p align="center">
@@ -15,9 +15,6 @@
   <a title="@visx/shape npm downloads" href="https://www.npmjs.com/package/@visx/shape">
     <img src="https://img.shields.io/npm/dm/@visx/shape.svg?style=flat-square" />
   </a>
-  <a title="Join the community on Spectrum" href="https://spectrum.chat/vx">
-    <img src="https://withspectrum.github.io/badge/badge.svg" />
-  </a>
   <a href="https://app.fossa.io/projects/git%2Bhttps%3A%2F%2Fgithub.com%2Fhshoff%2Fvx?ref=badge_shield" alt="FOSSA Status">     <img src="https://app.fossa.io/api/projects/git%2Bhttps%3A%2F%2Fgithub.com%2Fhshoff%2Fvx.svg?type=shield"/>
   </a>
   <a href="https://lernajs.io/" alt="lerna">