fix appveyor to use mysql as service (#3085)
fix appveyor to use mysql as service (#3085)

* fix appveyor to use mysql as service

* updated appveyor to use Mysql 5.7

tiger-seo/Codeception,tasselchof/Codeception,Codeception/base,janhenkgerritsen/Codeception,Codeception/base,hubbyist/Codeception,tasselchof/Codeception,Naktibalda/Codeception,Naktibalda/Codeception,Codeception/base,sergeyklay/Codeception,janhenkgerritsen/Codeception,Codeception/Codeception,kt81/Codeception,tiger-seo/Codeception,TehJoE/Codeception,TehJoE/Codeception,tasselchof/Codeception,kt81/Codeception,Codeception/Codeception,pitpit/Codeception,hubbyist/Codeception,Vreasy/Codeception,Vreasy/Codeception,pitpit/Codeception,sergeyklay/Codeception,Naktibalda/Codeception