vweb: fix typo in README.md (#19206)

Ikko Eltociear Ashimine · web-flow · commit ffea6eb52d57 · 2023-08-22T21:34:24.000+03:00
usefull -&gt; useful
diff --git a/vlib/vweb/README.md b/vlib/vweb/README.md
@@ -403,7 +403,7 @@ can think of it as a chain.
 
 ### Context values
 
-You can store a value pair in vweb's context. It is especially usefull for passing variables
+You can store a value pair in vweb's context. It is especially useful for passing variables
 from a middleware function to the route handler.
 
 **Example**:
