Tests fail on mono/linux when using latest dotnet 7 sdk

[dnperfors]

Describe the bug
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To Reproduce
Code example that reproduces the behavior:

[Fact]
public void Issue()
{
...
}

Expected behavior
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Background (please complete the following information):

• Version of library: [e.g. 0.10]
• Version of .NET: [e.g. 7.0]

Additional context
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[dnperfors]

Sometimes the build fails for mono with the following exception:

Error Message:
   System.BadImageFormatException : Method has zero rva
  Stack Trace:
    at TestableHttpClient.Tests.HttpRequestMessagesCheckExtensionsTests.WithHeaderName.WithHeader_WithNumberOfRequests_NullOrEmptyHeaderName_ThrowsArgumentNullException (System.String headerName) [0x0001d] in <bbb5375ffda3455a80a3e0ca0871039f>:0 
  at (wrapper managed-to-native) System.Reflection.RuntimeMethodInfo.InternalInvoke(System.Reflection.RuntimeMethodInfo,object,object[],System.Exception&)
  at System.Reflection.RuntimeMethodInfo.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x0006a] in <d636f104d[58](https://github.com/testablehttpclient/TestableHttpClient/actions/runs/6274680107/job/17040530289#step:9:59)046fd9b195699bcb1a744>:0