Update GHA that use VCPKG to support workflow trigger (#602)

Author: walbourn

.github/workflows/vcpkg.yml

@@ -26,6 +26,7 @@ on:
       - build/*.props
       - build/*.ps1
       - build/*.targets
+  workflow_dispatch: {}
 
 permissions:
   contents: read
@@ -126,7 +127,7 @@ jobs:
             gameinput: 'OFF'
 
     steps:
-      - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
+      - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
 
       - name: 'Install Ninja'
         run: choco install ninja