Updated GitHub Actions runner.

Ubuntu 20.04 is deprecated.

Author: orbitalquark

.github/workflows/release.yml

@@ -7,7 +7,7 @@ jobs:
   build:
     strategy:
       matrix:
-        os: [ubuntu-20.04, windows-2019, macOS-13, ubuntu-22.04-arm]
+        os: [ubuntu-22.04, windows-2019, macOS-13, ubuntu-22.04-arm]
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout