Better error message

Author: Happypig375

src/FSharpPlus/Parsing.fs

@@ -54,7 +54,7 @@ module Parsing =
                     if consumeNumericPlus then regex.Append @"\+?" |> ignore
                     "([0-9a-fA-F]+)"
                 | '%' -> "%"
-                | x -> failwith $"Unknown specifier: {x}"
+                | x -> failwith $"Unknown format specifier: {x}"
                 |> regex.Append |> ignore
                 if consumeSpacesAfter then regex.Append @"\s*" else regex
             | '\\' | '*' | '+' | '?' | '|' | '{' | '[' | '(' | ')' | '^' | '$' | '.' | '#' | ' ' as escape ->
@@ -182,4 +182,4 @@ module Parsing =
     /// Gets a tuple with the result of parsing each element of a formatted text from the Console. Returns None in case of failure.
     let inline tryScanfn pf : '``(T1 * T2 * ... * Tn)`` option = trySscanf pf (Console.ReadLine ())
 
-#endif
+#endif