CI: Bump to Ubuntu latest

Author: lz-bro

.github/workflows/spike-openocd-tests.yml

@@ -34,9 +34,9 @@ on:
 jobs:
   test:
     name: Test debug (Ubuntu)
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           submodules: recursive
 
@@ -166,7 +166,7 @@ jobs:
       - name: Archive test logs
         # Proceed even if there was a failed test
         if: ${{ success() || failure() }}
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: test-logs
           path: riscv-tests/debug/logs