ga: restore vcpkg git id, needed despite docs not mentioning it

.github/workflows/build.yml

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 06a9540..b3a70b8 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -21,6 +21,7 @@
         with:
           setupOnly: true
           vcpkgTriplet: x64-windows
+	  vcpkgGitCommitId: 5568f110b509a9fd90711978a7cb76bae75bb092
       - name: install dependencies (Windows)
         if: ${{ runner.os == 'Windows' }}
         run: |