fix doc: usEditContext to useEditContext

Author: usman-coe

docs/useEditContext.md

@@ -30,7 +30,7 @@ export const PostEdit = () => (
 );
 
 const Aside = () => {
-    const { record, isLoading } = usEditContext();
+    const { record, isLoading } = useEditContext();
     if (isLoading) return null;
     return (
         <div>
@@ -61,4 +61,4 @@ const {
     save, // the update callback, to be passed to the underlying form as submit handler
     saving, // boolean that becomes true when the dataProvider is called to update the record
 } = useEditContext();
-```
+```