feat: delete orphan remote tracking branches (#692)

* feat: remove orphan remote-tracking branches

- Allow user remove local remote-tracking branches without remotes (ie. remote was removed on merge request).
- Included 'DeleteRemoteTracking' and 'HasRemote' util methods to handle this case.

* fix: delete both case (local & remote-tracking)

- We have local and remote-tracking but not a remote branch. We need to remove both or only the tracking based on the checkbox and on the 'hasRemote' condition

src/Commands/Branch.cs

@@ -52,5 +52,27 @@
             cmd.Args = $"push {remote} --delete {name}";
             return cmd.Exec();
         }
+
+        public static bool DeleteRemoteTracking(string repo, string name)
+        {
+            var cmd = new Command();
+            cmd.WorkingDirectory = repo;
+            cmd.Context = repo;
+            cmd.Args = $"branch -D -r {name}";
+            return cmd.Exec();
+        }
+
+        public static bool HasRemote(string repo, string remote, string name)
+        {
+            var cmd = new Command();
+            cmd.WorkingDirectory = repo;
+            cmd.Context = repo;
+            cmd.SSHKey = new Config(repo).Get($"remote.{remote}.sshkey");
+            cmd.Args = $"ls-remote {remote} {name}";
+            
+            var rs = cmd.ReadToEnd();
+            
+            return rs.StdOut.Length > 0;
+        }
     }
 }