Updated CanRevertInObjectDatabase to not use a checkout and to just use commit refs.

Author: Jeremy Koritzinsky

LibGit2Sharp.Tests/RevertFixture.cs

@@ -518,14 +518,8 @@ public void CanRevertInObjectDatabase()
             string path = SandboxRevertTestRepo();
             using (var repo = new Repository(path))
             {
-
-
-                // Checkout the revert branch.
-                Branch branch = Commands.Checkout(repo, revertBranchName);
-                Assert.NotNull(branch);
-
                 // Revert tip commit.
-                var result = repo.ObjectDatabase.RevertCommit(repo.Head.Tip, repo.Head.Tip, 0, null);
+                var result = repo.ObjectDatabase.RevertCommit(repo.Branches[revertBranchName].Tip, repo.Branches[revertBranchName].Tip, 0, null);
                 Assert.Equal(MergeTreeStatus.Succeeded, result.Status);
             }
         }