chore: fix vcpkg root

Author: antoniaelsen

.github/workflows/build-test.yml

@@ -18,6 +18,7 @@ permissions:
 env:
   GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
   _VCPKG_: ${{ github.workspace }}/external/microsoft/vcpkg
+  VCPKG_ROOT: ${{ github.workspace }}/external/microsoft/vcpkg
   VCPKG_BINARY_SOURCES: "clear;x-gha,readwrite"
   VCPKG_DEFAULT_BINARY_CACHE: ${{ github.workspace }}/external/microsoft/vcpkg/bincache
   VCPKG_FEATURE_FLAGS: "dependencygraph"

README.md

@@ -14,7 +14,11 @@ To build:
 
 ```sh
 git submodule update --init
+
+# Set up vcpkg -- you can also use a vcpkg elsewhere via VCPKG_ROOT
 cd external/microsoft/vcpkg && ./bootstrap-vcpkg.sh && cd -
+export VCPKG_ROOT="$(pwd)/external/microsoft/vcpkg}"
+
 make all
 
 # or