naive attempt to use vcpkg

.gitlab-ci.yml

@@ -611,6 +611,7 @@ macOS12_Xcode13:
   - choco install ccache -y
   - choco install vswhere -y
   - choco install python -y
+  - vpkg install cxxopts
   - refreshenv
   - |
     function Make-SafeFileName {

CI/before_script.msvc.sh

@@ -554,7 +554,6 @@ if ! [ -z "$USE_CLANG_TIDY" ]; then
 fi
 
 BULLET_VER="2.89"
-CXXOPTS_VER="3.1.1"
 FFMPEG_VER="4.2.2"
 ICU_VER="70_1"
 LUAJIT_VER="v2.1.0-beta3-452-g7a0cf5fd"
@@ -595,11 +594,6 @@ if [ -z $SKIP_DOWNLOAD ]; then
 			"boost-${BOOST_VER}-msvc${MSVC_VER}-win${BITS}.exe"
 	fi
 
-  # cxxopts
-  download "cxxopts ${CXXOPTS_VER}" \
-    "https://github.com/jarro2783/cxxopts/archive/refs/tags/v${CXXOPTS_VER}.zip" \
-    "cxxopts-${CXXOPTS_VER}.zip"
-
 	# Bullet
 	download "Bullet ${BULLET_VER}" \
 		"https://gitlab.com/OpenMW/openmw-deps/-/raw/main/windows/Bullet-${BULLET_VER}-msvc${BULLET_MSVC_YEAR}-win${BITS}-double-mt.7z" \