Remove broken windows build

.appveyor.yml

@@ -1,29 +0,0 @@
-services:
-  - mongodb
-environment:
-  RUST_BACKTRACE: 1
-  OPENSSL_DIR: C:\Tools\vcpkg\packages\openssl-windows_x64-windows
-  BSON_LIB: C:\Tools\vcpkg\packages\libbson_x64-windows\lib
-  MONGO_LIB: C:\Tools\vcpkg\packages\mongo-c-driver_x64-windows\lib
-  SKIP_SSL_CONNECTION_TESTS: true
-  matrix:
-  - TARGET: x86_64-pc-windows-msvc
-install:
-  - curl -sSf -o rustup-init.exe https://win.rustup.rs/
-  - rustup-init.exe -y --default-host %TARGET%
-  - set PATH=%PATH%;C:\Users\appveyor\.cargo\bin;C:\Tools\vcpkg\installed\x64-windows\bin
-
-  - rustc -vV
-  - cargo -vV
-
-  - cd C:\Tools\vcpkg
-  - git pull -q
-  - .\bootstrap-vcpkg.bat
-  - vcpkg install openssl:x64-windows
-  - vcpkg install mongo-c-driver:x64-windows
-  - cd %APPVEYOR_BUILD_FOLDER%
-
-build: false
-test_script:
-  - cargo build
-  - cargo test