Application Insights has two types of tests - Classic (ping) and Standard. Validation Rules properties are only for Standard tests. You are probably setting classic ping test and thus those are not reflected. If you want to set Standard test kind should have value 'ping' and properties.kind should have value 'standard'. properties.Configuration should be set to null or not provided at all. Keep in mind that to ignore HTTP response properties.ValidationRules.ExpectedHttpStatusCode should be set to 0. If you want to do Classic text it is harder to do that as the configuration is provided as string in xml format via properties.Configuration.WebTest property.
Update: Forgot that there is a typo in this API. The property name is properties.ValidationRules.IgnoreHttpStatusCode . Note IgnoreHttpStatusCode not IgnoreHttpSStatusCode. No matter that the API reports that the property should be IgnoreHttpSStatusCode, it is actually IgnoreHttpStatusCode. See this thread.
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