update cmake toolchain path

Author: bavulapati

.github/workflows/build-javascriptcore.yml

@@ -11,4 +11,4 @@ jobs:
           ./vcpkg/bootstrap-vcpkg.bat
       - name: Build JavaScriptCore
         run: |
-          cmake -B build -S . -DCMAKE_TOOLCHAIN_FILE=.\vcpkg\scripts\buildsystems\vcpkg.cmake
+          cmake -B build -S . -DCMAKE_TOOLCHAIN_FILE=vcpkg\scripts\buildsystems\vcpkg.cmake