[ci] Update Ubuntu 20.04 images to 24.04

GitHub actions will start failing jobs using Ubuntu 20.04 images, so
switch to 24.04. Switch also on CircleCI while at it.

.circleci/config.yml

@@ -89,7 +89,7 @@ jobs:
 
   tsan:
     docker:
-      - image: ubuntu:20.04
+      - image: ubuntu:24.04
     steps:
       - checkout
       - run: apt update || true
@@ -104,7 +104,7 @@ jobs:
 
   msan:
     docker:
-      - image: ubuntu:20.04
+      - image: ubuntu:24.04
     steps:
       - checkout
       - run: apt update || true

.github/workflows/configs-build.yml

@@ -11,7 +11,7 @@ permissions:
 
 jobs:
   build:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-24.04
 
     steps:
     - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2

.github/workflows/linux-ci.yml

@@ -12,7 +12,7 @@ permissions:
 
 jobs:
   build:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-24.04
 
     steps:
     - name: Checkout