AppVeyor: Remove allowed failure build configuration

appveyor.yml

@@ -542,22 +542,6 @@ for:
       only:
         - configuration: Release
       fast_finish: false
-      allow_failures:
-        # Visual Studio 2019
-        - id: Full-VS2019-x64
-          compiler: msvc-21-seh
-          build_shared: NO
-          no_files: NO
-          enable_ipv6: YES
-          enable_ssl: YES
-          enable_websockets: YES
-          no_cgi: NO
-          no_caching: NO
-          enable_stats: YES
-          configuration: Release
-          platform: x64
-          APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
-
   -
     matrix:
       only: