Merge remote-tracking branch 'origin/v3.4'

Author: AArnott

src/NerdBank.GitVersioning/CloudBuildServices/VisualStudioTeamServices.cs

@@ -33,7 +33,8 @@ public IReadOnlyDictionary<string, string> SetCloudBuildNumber(string buildNumbe
 
         public IReadOnlyDictionary<string, string> SetCloudBuildVariable(string name, string value, TextWriter stdout, TextWriter stderr)
         {
-            (stdout ?? Console.Out).WriteLine($"##vso[task.setvariable variable={name};]{value}");
+            Utilities.FileOperationWithRetry(() =>
+                (stdout ?? Console.Out).WriteLine($"##vso[task.setvariable variable={name};]{value}"));
             return GetDictionaryFor(name, value);
         }
 

src/NerdBank.GitVersioning/VersionOptions.cs

@@ -934,6 +934,7 @@ public bool? SetVersionVariables
             /// <summary>
             /// Gets or sets options around how and whether to set the build number preset by the cloud build with one enriched with version information.
             /// </summary>
+            [JsonProperty(DefaultValueHandling = DefaultValueHandling.Ignore)]
             public CloudBuildNumberOptions? BuildNumber
             {
                 get => this.buildNumber;