Update README.md

Author: aeriforme

README.md

@@ -2,7 +2,7 @@
 
 This is a collection of [WarpX](https://github.com/BLAST-WarpX/warpx) tutorials, in lesson format.  
 
-Check out the [tutorial website](https://aeriforme.github.io/warpx-tutorials/).
+Check out the [tutorial website](https://github.com/BLAST-WarpX/warpx-tutorials).
 
 If you have any questions, contact [@aeriforme](https://github.com/aeriforme).