Fix GHA CI after they upgraded nodejs

They upgraded to a version that requires a glibc newer than is in the
pre-2023 ASWF containers.

See AcademySoftwareFoundation/OpenImageIO#4324

Signed-off-by: Cary Phillips <cary@ilm.com>

.github/workflows/ci_workflow.yml

@@ -222,6 +222,8 @@ jobs:
     env:
       CXX: ${{ matrix.cxx-compiler }}
       CC: ${{ matrix.cc-compiler }}
+      ACTIONS_RUNNER_FORCE_ACTIONS_NODE_VERSION: node16
+      ACTIONS_ALLOW_USE_UNSECURE_NODE_VERSION: true      
     steps:
       - name: Checkout
         uses: actions/checkout@f43a0e5ff2bd294095638e18286ca9a3d1956744 # v3.6.0