Disable dll copies by vcpkg to avoid race condition (#3412)

This variable is explained at:
 https://learn.microsoft.com/en-us/vcpkg/users/buildsystems/cmake-integration#vcpkg_applocal_deps

Parallel ninja builds call "vcpkg z-applocal" in parallel which
can creaate collisions.

X_VCPKG_APPLOCAL_DEPS_SERIALIZED (from #3408) did not resolve this
because CMake's Ninja generator inlines target post-build commands
directly into the linker rule and does not place them in the
terminal/console pool.

VCPKG_APPLOCAL_DEPS=OFF disables the post build copies. We still
need to find the dlls so the the build folder is added to the
path.

It should fix the issues we've been seeing on the Windows CI
with vcpkg.

.github/actions/setup-windows/action.yml

diff --git a/.github/actions/setup-windows/action.yml b/.github/actions/setup-windows/action.yml
index db453eb..a866a79 100644
--- a/.github/actions/setup-windows/action.yml
+++ b/.github/actions/setup-windows/action.yml
@@ -35,7 +35,9 @@
   ext-cache-hit:
     value: ${{ steps.cache.outputs.ext-cache-hit }}
   vcpkg-cmake-config:
-    value: ${{ steps.vcpkg.outputs.vcpkg-cmake-config != '' && format('{0} -DX_VCPKG_APPLOCAL_DEPS_SERIALIZED=ON', steps.vcpkg.outputs.vcpkg-cmake-config) || '' }}
+    # Disable vcpkg applocal deployment to prevent race conditions during parallel Ninja builds.
+    # Dependent DLLs are added to PATH instead.
+    value: ${{ steps.vcpkg.outputs.vcpkg-cmake-config != '' && format('{0} -DVCPKG_APPLOCAL_DEPS=OFF', steps.vcpkg.outputs.vcpkg-cmake-config) || '' }}
 runs:
   using: "composite"
   steps:
@@ -112,6 +114,13 @@
         mv ${{ github.workspace }}\tmp\rav1e-windows-msvc-sdk\lib\pkgconfig\* ${{ github.workspace }}\vcpkg\installed\x64-windows-release\lib\pkgconfig
       shell: pwsh
 
+    - name: Add dependent DLLs to PATH
+      if: env.AVIF_WIN_LIBRARIES != '' || inputs.codec-rav1e == 'SYSTEM'
+      run: |
+        echo "${{ github.workspace }}\vcpkg\installed\x64-windows-release\bin" >> $env:GITHUB_PATH
+        echo "${{ github.workspace }}\build" >> $env:GITHUB_PATH
+      shell: pwsh
+
     - uses: ./.github/actions/cache
       id: cache
       with:

CMakeLists.txt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e967765..ae2e6ec 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -45,11 +45,6 @@
 include(AvifExternalProjectUtils)
 include(GNUInstallDirs)
 
-# Prevent race condition when copying dependencies in parallel builds with vcpkg on Windows.
-if(WIN32 AND VCPKG_APPLOCAL_DEPS)
-    set(X_VCPKG_APPLOCAL_DEPS_SERIALIZED ON CACHE BOOL "Add USES_TERMINAL to VCPKG_APPLOCAL_DEPS to force serialization." FORCE)
-endif()
-
 option(AVIF_ENABLE_NODISCARD "Add [[nodiscard]] to some functions." OFF)
 
 # Set C11 as the default