Move mac pipeline to macos 11 and move legacy to qt 5.12 (sorry 10.11 users)

Author: jurplel

azure-pipelines.yml

@@ -21,11 +21,11 @@ jobs:
       linux:
         imageName: 'ubuntu-18.04'
       macos:
-        imageName: 'macOS-10.15'
+        imageName: 'macOS-11'
         qtVersion: '6.2.2'
       macosx:
         imageName: 'macOS-10.15'
-        qtVersion: '5.9.9'
+        qtVersion: '5.12.12'
         skipHardPlugins: 'true'
       win64:
         imageName: 'windows-2019'