fix: Change error style in Config (#2314)

Fix: #1886

Co-authored-by: Ayaz Salikhov <mathbunnyru@users.noreply.github.com>
Co-authored-by: Alex Kremer <akremer@ripple.com>
Co-authored-by: Sergey Kuznetsov <skuznetsov@ripple.com>

src/util/config/Error.hpp

@@ -46,7 +46,7 @@ struct Error {
      */
     Error(std::string_view key, std::string_view err)
         : error{
-              fmt::format("{} {}", key, err),
+              fmt::format("The value of {} {}", key, err),
           }
     {
     }