Fix locale issue for numeric string conversions

Created by: jnysteen

Using a generated .NET Core client from an application with a locale that formats numbers with a comma as a decimal separator will make the client send invalid numeric parameters to the API. Any numeric parameter with decimals will added to the URL with a comma ('0,15' instead of '0.15'), potentially breaking the API integration. In my specific use case, the API interpreted '0,15' as '15', resulting in pretty funky errors.

This commit ensures that parameters are parsed with the invariant culture, fixing the mentioned error.

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