Fix warnings

* missing awaits in test code

Author: patchandthat

src/CSharp/Rsk.AuthZen.Client.Test/AuthZenClientTests.cs

@@ -2560,7 +2560,7 @@ public async Task Evaluation_On404AfterRecheckingMetadata_ShouldThrowAuthZenRequ
         await sut.Evaluate(evaluationRequest);
         var act = async () => await sut.Evaluate(evaluationRequest);
 
-        act.Should().ThrowAsync<AuthZenRequestFailureException>();
+        await act.Should().ThrowAsync<AuthZenRequestFailureException>();
 
         calls.Should().Be(5);
 
@@ -2811,8 +2811,8 @@ public async Task BoxcarEvaluation_On404AfterRecheckingMetadata_ShouldThrowAuthZ
 
         await sut.Evaluate(evaluationRequest);
         var act = async () => await sut.Evaluate(evaluationRequest);
-
-        act.Should().ThrowAsync<AuthZenRequestFailureException>();
+        
+        await act.Should().ThrowAsync<AuthZenRequestFailureException>();
 
         calls.Should().Be(5);