Ensure library registration code is called only once before use

Question

I'm using a third party library, and as part of its requirements, I need to register a license key to it, before using it.

To help do this, I was thinking of having a helper class of form:

namespace SomeLibrary
{
    public static class LibraryHelper
    {
        public static void RegisterLicense()
        {
        }

        static LibraryHelper()
        {
            // call underlying library's code to register. Should only be called once.
            TheThirdPartyLibrary.RegisterLicenceKey("ABC");  
        }
    }
}

Then in the startup of my application (e.g. in Program.cs), I could call:

SomeLibrary.LibraryHelper.RegisterLicense(). 

The static constructor is just to ensure that TheThirdPartyLibrary.RegisterLicenceKey("ABC");
does not get called more than once. My understanding is that this should work, but the code looks a bit unusual having a RegisterLicense method that is empty. Are there any other alternatives ?