Update specs for new Result#call functionality

spec/helpers/result_call_spy.cr

@@ -1,10 +1,16 @@
 # Spy class for testing `Spectator::Result#call`.
 class ResultCallSpy
   {% for name in %i[success failure error pending] %}
-  getter! {{name.id}} : ::Spectator::Result
+  getter? {{name.id}} = false
+
+  def {{name.id}}
+    @{{name.id}} = true
+    {{name}}
+  end
 
   def {{name.id}}(arg)
-    @{{name.id}} = arg
+    @{{name.id}} = true
+    arg
   end
   {% end %}
 end