public override async Task <string?> OnSetPropertyValueAsync(string propertyName, string unevaluatedPropertyValue, IProjectProperties defaultProperties, IReadOnlyDictionary <string, string>?dimensionalConditions = null)
{
await _launchSettings.SetActiveProfileAsync(unevaluatedPropertyValue);
// We've intercepted the "set" operation and redirected it to the launch settings.
// Return "null" to indicate that the value should _not_ be set in the project file
// as well.
return(null);
}