Remove Ubuntu 20.04

Author: cmcgee1024

.github/workflows/pull_request.yml

@@ -24,7 +24,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        container: ["ubuntu:20.04", "ubuntu:22.04", "ubuntu:24.04", "redhat/ubi9", "debian:12", "fedora:39"]
+        container: ["ubuntu:22.04", "ubuntu:24.04", "redhat/ubi9", "debian:12", "fedora:39"]
     container:
       image: ${{ matrix.container }}
     steps: