AzP: Remove VS2015 job

.azure-pipelines.yml

@@ -81,31 +81,6 @@ jobs:
           cxxver: '17'
           use_conan: 'ON'
 
-  - job: 'win2012_vs2015_cmake'
-    pool:
-      vmImage: 'vs2015-win2012r2'
-    steps:
-      - powershell: |
-          Invoke-WebRequest https://cmake.org/files/v3.14/cmake-3.14.4-win64-x64.zip -OutFile C:\cmake-3.14.4-win64-x64.zip
-          Expand-Archive C:\cmake-3.14.4-win64-x64.zip -DestinationPath C:\
-          Rename-Item -Path C:\cmake-3.14.4-win64-x64 -NewName C:\cmake
-          Write-Host "##vso[task.prependpath]C:\cmake\bin"
-        displayName: 'Install CMake 3.14'
-      - template: .ci/azure-pipelines/steps-check-cmake.yml
-      - powershell: |
-          Invoke-WebRequest https://www.python.org/ftp/python/3.7.1/python-3.7.1-amd64-webinstall.exe -OutFile C:\py3-setup.exe
-          C:\py3-setup.exe /quiet PrependPath=1 InstallAllUsers=1 Include_launcher=1 InstallLauncherAllUsers=1 Include_test=0 Include_doc=0 Include_dev=0 Include_debug=0 Include_tcltk=0 TargetDir=C:\Python37 | Out-Null
-          Write-Host "##vso[task.prependpath]C:\Python37"
-          Write-Host "##vso[task.prependpath]C:\Python37\Scripts"
-        displayName: 'Install Python 3.7'
-      - template: .ci/azure-pipelines/steps-install-conan.yml
-        parameters:
-          python: C:\Python37\python.exe
-      - template: .ci/azure-pipelines/steps-install-boost.yml
-      - template: .ci/azure-pipelines/steps-cmake-build-and-test.yml
-        parameters:
-          use_conan: 'ON'
-
   - job: 'macos1014_xcode11_cmake'
     pool:
       vmImage: 'macOS-10.14'