chore: update readme with link to fleek (#337)

Author: SgtPooki

README.md

@@ -2,7 +2,9 @@
 
 **A site displaying public IPFS gateways and their online/offline status.**
 
-View the Public Gateway Checker on GitHub Pages: https://ipfs.github.io/public-gateway-checker/
+View the Public Gateway Checker in action
+* on Fleek:  https://ipfs-public-gateway-checker.on.fleek.co/
+* on GitHub Pages: https://ipfs.github.io/public-gateway-checker/
 
 [![Screenshot of Public Gateway Checker](https://user-images.githubusercontent.com/157609/121263486-f7fb2800-c8b5-11eb-9061-0b6f586a6f25.png)](https://ipfs.github.io/public-gateway-checker/)