try ubuntu 20.04 as it works for assimp

Author: dellis1972

.github/workflows/main.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [windows-latest, macos-latest, ubuntu-22.04]
+        os: [windows-latest, macos-latest, ubuntu-20.04]
       fail-fast: false
     steps:
       - name: Expose GitHub Runtime