Fix setting VCPKG_ROOT in the cmd one liner. (#988)

* Fix setting VCPKG_ROOT broken in #947

* Update scripts sha and add release checklist for VS.

manual-testing/deploy-to-vs.md

@@ -0,0 +1,68 @@
+Updating the copy of vcpkg shipped with VS
+
+1. Update the copy of vcpkg in default.config in the VS repo.
+2. Submit a PR which will give you a prototype of VS with that vcpkg inside.
+3. Install the prototype version of VS with the vcpkg inserted. Ensure the native desktop workload is selected, and that vcpkg and cmake bits are installed. Don't forget about preinstall.
+4. Open a developer command prompt and run `vcpkg integrate install` (this step hopefully removed soon)
+    * This also verifies that vcpkg installed into the developer command prompt correctly.
+5. Create a new C++ console project.
+6. Turn on diagnostic logging.
+    * Tools -> Options: Projects and Solutions\Build and Run\\MSBuild project output verbosity
+7. Build the console project, check that vcpkg isn't affecting that project:
+    * Lib AdditionalLibraryDirectories doesn't contain a hypothetical vcpkg installed directory
+    * Target VcpkgInstallManifestDependencies doesn't run
+    * Target AppLocalFromInstalled doesn't run
+8. In the developer command prompt cd to the directory with the vcxproj for the console app and run:
+```
+vcpkg new --application
+vcpkg add port zlib
+```
+9. Rebuild the console app, and verify the manifest mode warning is printed:
+
+```
+1>Target "VcpkgCheckManifestRoot" in file "C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\vcpkg\scripts\buildsystems\msbuild\vcpkg.targets":
+1>  Task "Error" skipped, due to false condition; ('$(VcpkgEnableManifest)' == 'true' and '$(_ZVcpkgManifestRoot)' == '') was evaluated as ('false' == 'true' and 'C:\Users\bion\source\repos\ConsoleApplication3\ConsoleApplication3\' == '').
+1>  Task "Message"
+1>    Task Parameter:Importance=High
+1>    Task Parameter:Text=The vcpkg manifest was disabled, but we found a manifest file in C:\Users\bion\source\repos\ConsoleApplication3\ConsoleApplication3\. You may want to enable vcpkg manifests in your properties page or pass /p:VcpkgEnableManifest=true to the msbuild invocation.
+1>    The vcpkg manifest was disabled, but we found a manifest file in C:\Users\bion\source\repos\ConsoleApplication3\ConsoleApplication3\. You may want to enable vcpkg manifests in your properties page or pass /p:VcpkgEnableManifest=true to the msbuild invocation.
+1>  Done executing task "Message".
+```
+10. Right click the console application, properties, and in the property pages change vcpkg\\Use vcpkg Manifest to "Yes"
+11. Rebuild the project, observe vcpkg builds zlib.
+12. Change the .cpp to:
+```
+#include <iostream>
+#include <zlib.h>
+
+int main()
+{
+    std::cout << "Hello World!\n" << ZLIB_VERSION;
+}
+```
+13. Run the program and verify that a reasonable zlib version is printed.
+14. Close Visual Studio.
+15. In the directory of that vcxproj, create a CMakeLists.txt with the following content:
+```
+cmake_minimum_required(VERSION 3.24)
+project(console-app LANGUAGES CXX)
+message(WARNING "CMake Version is ${CMAKE_VERSION}")
+find_package(ZLIB REQUIRED)
+file(GLOB PROGRAM_SOURCES *.cpp)
+add_executable(program ${PROGRAM_SOURCES})
+target_link_libraries(program PRIVATE ZLIB::ZLIB)
+```
+16. Back in the developer command prompt, run:
+```
+cmake -G Ninja -DCMAKE_TOOLCHAIN_FILE="%VCPKG_ROOT%\scripts\buildsystems\vcpkg.cmake" -S . -B build_msvc
+ninja -C build_msvc
+build_msvc\program.exe
+```
+and check that a reasonable zlib version is printed.
+17. Back in the developer command prompt, verify that the copy of CMake can be customized by running:
+```
+cmake -G Ninja -DCMAKE_TOOLCHAIN_FILE="%VCPKG_ROOT%\scripts\buildsystems\vcpkg.cmake" -S . -B build_artifact
+ninja -C build_artifact
+build_artifact\program.exe
+```
+and check that the cmake version acquired by artifacts is printed during the cmake configure, and that a reasonable zlib version is printed.

vcpkg-init/vcpkg-init.ps1

@@ -113,7 +113,7 @@ IF EXIST "%~dp0.vcpkg-root" (
 )
 
 IF "%VCPKG_ROOT:~-1%"=="\" (
-  SET VCPKG_ROOT=%VCPKG_ROOT:0,-1%
+  SET VCPKG_ROOT=%VCPKG_ROOT:~0,-1%
 )
 
 IF "%VCPKG_ROOT%"=="" (

vcpkg-init/vcpkg-scripts-sha.txt

@@ -1 +1 @@
-ec96844b8b1515d8982b134c73d7bc2b248d2c42
+84df5613f71eda8a73ab08dc3041f3af7103a5b2