PR feedback

Author: qmfrederik

src/NerdBank.GitVersioning/CloudBuildServices/GitLab.cs

@@ -17,7 +17,7 @@ internal class GitLab : ICloudBuild
             Environment.GetEnvironmentVariable("CI_COMMIT_TAG") == null ? 
                 $"refs/heads/{Environment.GetEnvironmentVariable("CI_COMMIT_REF_NAME")}" : null;
 
-        public string BuildingRef => this.BuildingBranch != null ? this.BuildingBranch : this.BuildingTag;
+        public string BuildingRef => this.BuildingBranch ?? this.BuildingTag;
 
         public string BuildingTag =>
             Environment.GetEnvironmentVariable("CI_COMMIT_TAG") != null ?