GitLab CI/CD: Modify the build script for Windows

The build script is modified to run on the current Windows build
machines (including the Win10 VM).

.gitlab-ci.yml

@@ -18,25 +18,20 @@ mac:
     - build/*dmg
     expire_in: 10 days
 
+
+# To test the GitLab process _locally_ on MS-Windows with powershell (pwsh),
+# go to the root Git directory, and run:
+# C:\GitLab-Runner\gitlab-runner.exe exec shell --shell pwsh --builds-dir <gitlab build-dir> <job-name>
+
 windows:
   tags:
-  - Windows
+    - Windows
   stage: build
+  variables:
+    GIT_DEPTH: 1 # shallow cloning
   script:
-    - set OPTLIBS=C:\opt\x64
-    - set CCACHE_DIR=C:\opt\ccache
-    - New-Item -ItemType "directory" -Confirm:$false -Force:$true -Name "build"
-    - $Env:Path
-    - cd build
-    - cmd.exe "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars64.bat"
-    - cmake --version
-    - cmake -G "Visual Studio 16 2019" -A x64 -T host=x64 -DLIB_MAN=OFF -DQTDIR=C:/Qt/5.14.1/msvc2017_64 -DCPACK_IFW_ROOT=C:\Qt\Tools\QtInstallerFramework\3.2 -DCMAKE_INCLUDE_PATH=%OPTLIBS%/include -DCMAKE_LIBRARY_PATH=%OPTLIBS%/lib -DCMAKE_CXX_COMPILER_LAUNCHER=ccache -DCMAKE_C_COMPILER="cl.exe" -DCMAKE_CXX_COMPILER="cl.exe" -B. ..
-    - ccache -z
-    - ccache -p
-    - cmake --build . --config Release
-    - Get-Location
-    - ctest -C Release --output-on-failure
-    - cpack -C Release --verbose
+    # run local Powershell script
+    - ./winbuild.ps1
   artifacts:
     paths:
     - build/*.exe