Merge pull request #27 from dmnyu/copilot/sub-pr-26

[WIP] Address feedback from review on release v0.2.5 alpha

Author: dmnyu

bagit.net/services/TagFileService.cs

@@ -102,7 +102,10 @@ public void ValidateBagitTXT(string bagRoot)
         {
             var bagitPath = Path.Combine(bagRoot, "bagit.txt");
             if (!File.Exists(bagitPath))
+            {
                 _messageService.Add(new MessageRecord(MessageLevel.ERROR, $"bagit.txt is missing from {bagRoot}."));
+                return;
+            }
             var tags = GetTagFileAsDict(bagitPath);
 
             if (!tags.TryGetValue("BagIt-Version", out var version))