Make BranchModel dependency IGitService explicit

Be explicit when BranchModel constructor depends on IGitService.

Author: jcansdale

src/GitHub.Exports/Models/BranchModel.cs

@@ -26,13 +26,13 @@ public BranchModel(Octokit.Branch branch, IRepositoryModel repo)
             Id = String.Format(CultureInfo.InvariantCulture, "{0}/{1}", Repository.Owner, Name);
         }
 
-        public BranchModel(LibGit2Sharp.Branch branch, IRepositoryModel repo)
+        public BranchModel(LibGit2Sharp.Branch branch, IRepositoryModel repo, IGitService gitService)
         {
             Extensions.Guard.ArgumentNotNull(branch, nameof(branch));
             Extensions.Guard.ArgumentNotNull(repo, nameof(repo));
             Name = DisplayName = branch.FriendlyName;
 #pragma warning disable 0618 // TODO: Replace `Branch.Remote` with `Repository.Network.Remotes[branch.RemoteName]`.
-            Repository = branch.IsRemote ? new LocalRepositoryModel(branch.Remote.Url, GitService.GitServiceHelper) : repo;
+            Repository = branch.IsRemote ? new LocalRepositoryModel(branch.Remote.Url, gitService) : repo;
 #pragma warning restore 0618
             IsTracking = branch.IsTracking;
             Sha = branch.Tip?.Sha;

src/GitHub.Exports/Models/LocalRepositoryModel.cs

@@ -183,7 +183,7 @@ public IBranch CurrentBranch
                 // BranchModel doesn't keep a reference to Repository
                 using (var repo = gitService.GetRepository(LocalPath))
                 {
-                    return new BranchModel(repo?.Head, this);
+                    return new BranchModel(repo?.Head, this, gitService);
                 }
             }
         }