Cirrus CI: get rid of the Windows task. [skip ci]

There are CI platforms that are useful for doing Windows CI using Visual
Studio.  It appears that Cirrus CI is not one of them, as they don't
appear to have images with VS pre-installed, and it does appear that
using Chocolatey to install it takes a long time.

Author: guyharris

.cirrus.yml

@@ -58,36 +58,6 @@ macos_task:
     - brew install openssl@3
     - ./build_matrix.sh
 
-#
-# Just testing for now.
-#
-windows_task:
-  name: windows-amd64
-  only_if: $CIRRUS_BRANCH != 'coverity_scan'
-  windows_container:
-    image: cirrusci/windowsservercore:2019
-  env:
-    MAKE_BIN: msbuild
-    MAKEFLAGS: '/m /nologo /m /nologo /p:Configuration=Release'
-    MATRIX_CC: cl
-    MATRIX_CMAKE: yes
-    MSYSTEM: MINGW64
-  install_script:
-    - dir/a "C:\Program Files (x86)"
-    - choco install -y --no-progress --limit-output visualstudio2019-workload-vctools --package-parameters "--includeOptional"
-    - choco install --no-progress -y winflexbison
-    - win_flex --version
-    - win_bison --version
-    - choco install --no-progress -y curl
-    - curl -O -s https://www.winpcap.org/install/bin/WpdPack_4_1_2.zip
-    - 7z x .\WpdPack_4_1_2.zip -oc:\projects\libpcap\Win32
-    - curl -O -s https://npcap.com/dist/npcap-sdk-1.13.zip
-    - 7z x .\npcap-sdk-1.13.zip -oc:\projects\libpcap\Win32\npcap-sdk
-    - curl -o AirPcap_Devpack.zip -L -s "https://support.riverbed.com/bin/support/download?sid=l3vk3eu649usgu3rj60uncjqqu"
-    - 7z x .\AirPcap_Devpack.zip -oc:\projects\libpcap\Win32
-  script:
-   - sh -lc ./build_matrix.sh
-
 coverity_task:
   name: Coverity Scan
   only_if: $CIRRUS_BRANCH == 'coverity_scan'