Fix: [CI] Installed (and cached) vcpkg packages are never upgraded in release-linux workflow (#11396)

Other workflows use a per image cache because images provide a fixed vcpkg clone.

.github/workflows/release-linux.yml

@@ -116,6 +116,9 @@ jobs:
           cd /vcpkg
           ./bootstrap-vcpkg.sh -disableMetrics
 
+          # Once installed (and cached) a package will never be upgraded unless we do it ourselves.
+          ./vcpkg upgrade --no-dry-run
+
           # Make Python3 available for other packages.
           ./vcpkg install python3
           ln -sf $(pwd)/installed/x64-linux/tools/python3/python3.[0-9][0-9] /usr/bin/python3