Fix appveyor, remove MinGW because of Qt6

Author: paceholder

.appveyor.yml

@@ -2,30 +2,25 @@ clone_depth: 5
 
 environment:
   matrix:
-    - GENERATOR : "Visual Studio 16 2019"
+    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
+      GENERATOR : "Visual Studio 16 2019"
+      ARCHITECTURE : "-A Win32" 
+      QTDIR: C:\Qt\5.15\msvc2019
+      QT_MAJOR: 5
+      PLATFORM: Win32
+    - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
+      GENERATOR : "Visual Studio 16 2019"
       ARCHITECTURE : "-A x64"
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
-      QTDIR: C:\Qt\5.15.2\msvc2019_64
+      QTDIR: C:\Qt\6.2.2\msvc2019_64
+      QT_MAJOR: 6
       PLATFORM: x64
-    - GENERATOR : "Visual Studio 15 2017"
-      ARCHITECTURE : ""
-      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
-      QTDIR: C:\Qt\5.15.2\msvc2017
-      PLATFORM: Win32
-    - GENERATOR : "MinGW Makefiles"
-      ARCHITECTURE : ""
-      QTDIR: C:\Qt\5.11.3\mingw53_32
-      PLATFORM: x86
-      CMAKE_CXX_FLAGS_INIT: -DCATCH_CONFIG_NO_CPP11_TO_STRING
 
 configuration:
   - Release
 
 install:
   - set PATH=%QTDIR%\bin;%PATH%
-  - set Qt5_DIR=%QTDIR%\lib\cmake\Qt5
-  - set PATH=C:\MinGW\bin;C:\MinGW\msys\1.0;%PATH%
-  - set PATH=C:\Qt\Tools\mingw530_32;%PATH%
+  - set Qt%QT_MAJOR%_DIR=%QTDIR%\lib\cmake\Qt%QT_MAJOR%
   - set PATH=%PATH:C:\Program Files\Git\usr\bin=% # trick to remove sh.exe
 
 before_build:

CMakeLists.txt

@@ -46,7 +46,7 @@ find_package(Qt6
 )
 
 if (NOT Qt6_FOUND)
-  find_package(Qt5 5.15
+  find_package(Qt5 5.13
     COMPONENTS
      Core
      Widgets