CI - fix appveyor build WIP

https://ci.appveyor.com/project/zdenekdrahos/phpqa/builds/27090850
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appveyor.yml

@@ -2,7 +2,7 @@ platform:
     - x64
 environment:
     matrix:
-        - php_version: 7.0
+        - php_version: 7.1
 
 branches:
     except: