Interpreter unit tests are failing on AppVeyor

[DonJayamanne]

  1) Interpreters from Windows Registry
       Must default names for PythonCore and exe:
     AssertionError: Incorrect version
      at Object.<anonymous> (C:\projects\vscode-python-v3vd6\src\test\interpreters\windowsRegistryService.test.ts:88:20)
      at Generator.next (<anonymous>)
      at fulfilled (C:\projects\vscode-python-v3vd6\out\test\interpreters\windowsRegistryService.test.js:4:58)
      at <anonymous>
  2) Interpreters from Windows Registry
       Must return a single entry and when registry contains only the InstallPath:
     AssertionError: Incorrect version
      at Object.<anonymous> (C:\projects\vscode-python-v3vd6\src\test\interpreters\windowsRegistryService.test.ts:123:20)
      at Generator.next (<anonymous>)
      at fulfilled (C:\projects\vscode-python-v3vd6\out\test\interpreters\windowsRegistryService.test.js:4:58)
      at <anonymous>
  3) Interpreters from Windows Registry
       Must return multiple entries:
     AssertionError: Incorrect version
      at Object.<anonymous> (C:\projects\vscode-python-v3vd6\src\test\interpreters\windowsRegistryService.test.ts:165:20)
      at Generator.next (<anonymous>)
      at fulfilled (C:\projects\vscode-python-v3vd6\out\test\interpreters\windowsRegistryService.test.js:4:58)
      at <anonymous>
  4) Interpreters from Windows Registry
       Must return multiple entries excluding the invalid registry items and duplicate paths:
     AssertionError: Incorrect version
      at Object.<anonymous> (C:\projects\vscode-python-v3vd6\src\test\interpreters\windowsRegistryService.test.ts:224:20)
      at Generator.next (<anonymous>)
      at fulfilled (C:\projects\vscode-python-v3vd6\out\test\interpreters\windowsRegistryService.test.js:4:58)
      at <anonymous>
  5) Interpreters from Windows Registry
       Must return multiple entries excluding the invalid registry items and nonexistent paths:
     AssertionError: 1. Incorrect version
      at Object.<anonymous> (C:\projects\vscode-python-v3vd6\src\test\interpreters\windowsRegistryService.test.ts:284:20)
      at Generator.next (<anonymous>)
      at fulfilled (C:\projects\vscode-python-v3vd6\out\test\interpreters\windowsRegistryService.test.js:4:58)
      at <anonymous>