fix typo

actix-macros/src/lib.rs

@@ -67,7 +67,7 @@ pub fn main(args: TokenStream, item: TokenStream) -> TokenStream {
                     }
                 },
                 _ => {
-                    return syn::Error::new_spanned(arg, "Unkown attribute specified")
+                    return syn::Error::new_spanned(arg, "Unknown attribute specified")
                         .to_compile_error()
                         .into();
                 }

actix-macros/tests/trybuild/main-06-unknown-attr.stderr

@@ -1,4 +1,4 @@
-error: Unkown attribute specified
+error: Unknown attribute specified
  --> $DIR/main-06-unknown-attr.rs:1:18
   |
 1 | #[actix_rt::main(foo = "bar")]