missing parenthesis on Test-Path.

Signed-off-by: FrancisANDRE <zosrothko@orange.fr>

appveyor.yml

@@ -157,7 +157,7 @@ install:
   - ps: |
       if ($env:platform -eq "Win32")
       {
-          if (Test-Path "c:\mysql-5.7.9-win32" -and False) {
+          if ((Test-Path "c:\mysql-5.7.9-win32") -and False) {
               echo "using c:\mysql-5.7.9-win32 from cache"
           }
           else