Simplify IncrementCounter assert

When the assert fails it will look like this:
```
Test
'IncrementCounter_Showing_Default_Tab("https://enterprise.com",True,1,"xxx")'
 failed:
 NSubstitute.Exceptions.ReceivedCallsException : Expected to receive
exactly 1 call matching:
 IncrementCounter(x => (Convert(x.Body).Member.Name ==
value(GitHub.App.UnitTests.ViewModels.Dialog.Clone.RepositoryCloneViewModelTests+<>c__DisplayClass2_0).counterName))
Actually received no matching calls.
Received 1 non-matching call (non-matching arguments indicated with '*'
characters):
 IncrementCounter(*model => model.NumberOfCloneViewUrlTab*)
```

Author: jcansdale

test/GitHub.App.UnitTests/ViewModels/Dialog/Clone/RepositoryCloneViewModelTests.cs

@@ -45,11 +45,11 @@ public async Task Default_SelectedTabIndex_For_Group(string address, bool isGrou
             Assert.That(target.SelectedTabIndex, Is.EqualTo(expectTabIndex));
         }
 
-        [TestCase("https://github.com", false, nameof(UsageModel.MeasuresModel.NumberOfCloneViewGitHubTab))]
-        [TestCase("https://enterprise.com", false, nameof(UsageModel.MeasuresModel.NumberOfCloneViewEnterpriseTab))]
-        [TestCase("https://github.com", true, nameof(UsageModel.MeasuresModel.NumberOfCloneViewUrlTab))]
-        [TestCase("https://enterprise.com", true, nameof(UsageModel.MeasuresModel.NumberOfCloneViewUrlTab))]
-        public async Task IncrementCounter_Showing_Default_Tab(string address, bool isGroupA, string expectCounter)
+        [TestCase("https://github.com", false, 1, nameof(UsageModel.MeasuresModel.NumberOfCloneViewGitHubTab))]
+        [TestCase("https://enterprise.com", false, 1, nameof(UsageModel.MeasuresModel.NumberOfCloneViewEnterpriseTab))]
+        [TestCase("https://github.com", true, 1, nameof(UsageModel.MeasuresModel.NumberOfCloneViewUrlTab))]
+        [TestCase("https://enterprise.com", true, 1, nameof(UsageModel.MeasuresModel.NumberOfCloneViewUrlTab))]
+        public async Task IncrementCounter_Showing_Default_Tab(string address, bool isGroupA, int numberOfCalls, string counterName)
         {
             var cm = CreateConnectionManager(address);
             var connection = cm.Connections[0];
@@ -60,8 +60,9 @@ public async Task IncrementCounter_Showing_Default_Tab(string address, bool isGr
 
             await target.InitializeAsync(connection).ConfigureAwait(false);
 
-            var counter = await GetIncrementedCounter(usageTracker);
-            Assert.That(counter, Is.EqualTo(expectCounter));
+            await usageTracker.Received(numberOfCalls).IncrementCounter(
+                Arg.Is<Expression<Func<UsageModel.MeasuresModel, int>>>(x =>
+                    ((MemberExpression)x.Body).Member.Name == counterName));
         }
 
         [Test]
@@ -363,13 +364,5 @@ static IRepositoryModel CreateRepositoryModel(string owner, string name)
             repository.Name.Returns(name);
             return repository;
         }
-
-        static async Task<string> GetIncrementedCounter(IUsageTracker usageTracker)
-        {
-            await usageTracker.Received(1).IncrementCounter(Arg.Any<Expression<Func<UsageModel.MeasuresModel, int>>>()).ConfigureAwait(false);
-            var expression = (Expression<Func<UsageModel.MeasuresModel, int>>)usageTracker.ReceivedCalls().First().GetArguments()[0];
-            var counter = ((MemberExpression)expression.Body).Member.Name;
-            return counter;
-        }
     }
 }