title: F# type inferrence issue
body: <p>I have experienced the following problem while writing a test. Please find a  picture bellow.</p>
  
  <p><img src="https://i.stack.imgur.com/bNtaB.png" alt="enter image description here"></p>
  
  <p>If I create validateGameExistance function in the unit test project then it works fine.</p>
  
  <p>How could it be solved?</p>