Update Ubuntu image used in CI to latest LTS

Author: sgued

.github/workflows/ci.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-24.04
     steps:
       - uses: actions/checkout@v2
       - uses: actions-rs/toolchain@v1