add missing VALUETUPLE check

[SimonCropp]

VALUETUPLE was being used but not defined in any constants

#if VALUETUPLE
            if (definition == typeof(ValueTuple<>) || definition == typeof(ValueTuple<,>) ||
                definition == typeof(ValueTuple<,,>) || definition == typeof(ValueTuple<,,,>) ||
                definition == typeof(ValueTuple<,,,,>) || definition == typeof(ValueTuple<,,,,,>) ||
                definition == typeof(ValueTuple<,,,,,,>))
#else
            // ReSharper disable once PossibleNullReferenceException
            if (definition.FullName is
                "System.ValueTuple`1" or
                "System.ValueTuple`2" or
                "System.ValueTuple`3" or
                "System.ValueTuple`4" or
                "System.ValueTuple`5" or
                "System.ValueTuple`6" or
                "System.ValueTuple`7")
#endif

[SimonCropp]

side note is there any real value in doing type check here? wouldn't definition.FullName.StartsWith("System.ValueTuple``" suffice

[skomis-mm]

Looks good 👍

wouldn't definition.FullName.StartsWith("System.ValueTuple``" suffice

I think since we constrain max length of the tuple to 8 for destructuring, type name checks against interned strings should perform a bit better than StartsWith(..)