TF-2580: ci: Upgrade to ubuntu-24.04

This commit upgrades the Github Actions runner used for CI jobs to use
image `ubuntu-24.04` instead of `ubuntu-20.04`, as the latter image's
retirement is imminent.

Author: p--b

.github/workflows/ci.yml

@@ -6,7 +6,7 @@ on:
 
 jobs:
   BuildLinux:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-24.04
     steps:
       - uses: actions/checkout@v3