Fixed AppVeyor logo url

Signed-off-by: Timor Gruber <timor.gruber@gmail.com>

Author: MrPointer

README.md

@@ -1,6 +1,6 @@
 # Arduino-CMake NG
 
-[![AppVeyor](https://img.shields.io/appveyor/ci/arduino-cmake/arduino-cmake-ng/develop.svg?label=Windows&logo=appveyor)](https://ci.appveyor.com/api/projects/status/github/arduino-cmake/arduino-cmake-ng?svg=true)[![Travis CI](https://img.shields.io/travis/arduino-cmake/Arduino-CMake-NG.svg?label=Linux%20and%20OS%20X&logo=travis)](https://travis-ci.org/arduino-cmake/Arduino-CMake-NG)
+[![AppVeyor](https://img.shields.io/appveyor/ci/arduino-cmake/arduino-cmake-ng/develop.svg?label=Windows&logo=appveyor)](https://ci.appveyor.com/project/arduino-cmake/arduino-cmake-ng)[![Travis CI](https://img.shields.io/travis/arduino-cmake/Arduino-CMake-NG.svg?label=Linux%20and%20OS%20X&logo=travis)](https://travis-ci.org/arduino-cmake/Arduino-CMake-NG)
 
 **Arduino-CMake** is a framework which allows developers to write Arduino-based programs using any tool that supports cmake. *Arduino-based*? There are many other frameworks out there built upon Arduino's base, such as ESP32, and **we support that**.
 In other words, developers can use their favorite IDEs or text editors on their favorite OS to develop Arduino programs!