Fix more warnings

Suppress "CA1034:Nested types should not be visible" for unit tests.
Use the expectSha variable.

Author: jcansdale

test/GitHub.Exports.UnitTests/GitServiceTests.cs

@@ -71,7 +71,7 @@ public async Task EmptyRepository_ReturnsNull()
 
                 var sha = await target.GetLatestPushedSha(dir).ConfigureAwait(false);
 
-                Assert.That(sha, Is.Null);
+                Assert.That(sha, Is.EqualTo(expectSha));
             }
         }
 
@@ -255,11 +255,11 @@ static void AddTrackedBranch(Repository repo, Branch branch, Commit commit,
             repo.Branches.Update(branch, b => b.TrackedBranch = canonicalName);
         }
 
-        public async Task IntergrationTest()
+        public static async Task IntergrationTest()
         {
             var path = @"C:\Source\github.com\dotnet\roslyn";
             var gitService = new GitService(new RepositoryFacade());
-            var sha = await gitService.GetLatestPushedSha(path);
+            var sha = await gitService.GetLatestPushedSha(path).ConfigureAwait(false);
             Console.WriteLine(sha);
         }
     }

test/GitHub.Exports.UnitTests/GlobalSuppressions.cs

@@ -4,6 +4,10 @@
 // Project-level suppressions either have no target or are given 
 // a specific target and scoped to a namespace, type, member, etc.
 
-[assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Naming", "CA1707:Identifiers should not contain underscores", Justification = "Unit test names can contain a _")]
-[assembly: System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1034:Nested types should not be visible", Justification = "Nested unit test classes should be visible", Scope = "type")]
+[assembly: System.Diagnostics.CodeAnalysis.SuppressMessage(
+    "Naming", "CA1707:Identifiers should not contain underscores",
+    Justification = "Unit test names can contain a _")]
 
+[assembly: System.Diagnostics.CodeAnalysis.SuppressMessage(
+    "Design", "CA1034:Nested types should not be visible",
+    Justification = "Nested unit test classes should be visible")]