Fix typo in foundation.mdx (#650)

Author: StewartThomson

docs/layers/foundation.mdx

@@ -16,7 +16,7 @@ import ReactPlayer from 'react-player';
 <Steps>
 
   <Step>
-    ## <StepNumber/> Set up you project
+    ## <StepNumber/> Set up your project
 
     <Steps>
       1. Create a GitHub repository to host your infrastructure toolchain and configurations.