Fix culture-insensitive handling of numbers in RangeAttribute

[bkoelman]

Pull Request

The issue or feature being addressed

Fix for #3283 (comment): do not read/write fractional numbers in the current culture, which depends on OS-level settings, potentially resulting in unparsable JSON.

Details on the issue fix or feature implementation

According to https://json-schema.org/understanding-json-schema/reference/numeric#number, exponents are allowed, which is why I combined the flags:

[Flags]
public enum NumberStyles
{
    Number = AllowThousands | AllowDecimalPoint | AllowTrailingSign | Integer,
    Float = AllowExponent | AllowDecimalPoint | Integer
}

[martincostello]

Thanks for the fix.

I'm away from a proper computer for the next few days, otherwise I'd do this myself - would you be able to add/update a test somewhere to use a non en-US culture that would hit this bug so we can catch any regression in the future please?

[bkoelman]

I considered that for a moment, but couldn't find the right place to add such a test. There's no urgency to get this in, I don't mind if you take it from here once you have time.

[martincostello]

Test added in #3431 which will be merged into #3283 shortly.

[martincostello]

The test flushed out a bug with the values not round-tripping correctly. Fixed with 9e6dedf.