Bump ubuntu from 20.04 to 24.04 in /docker

Bumps ubuntu from 20.04 to 24.04.

---
updated-dependencies:
- dependency-name: ubuntu
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

docker/Dockerfile.withlib

@@ -7,7 +7,7 @@ ADD . /k8s-vgpu
 ARG GOPROXY=https://goproxy.cn,direct
 RUN cd /k8s-vgpu && make all
 
-FROM ubuntu:20.04
+FROM ubuntu:24.04
 ENV NVIDIA_DISABLE_REQUIRE="true"
 ENV NVIDIA_VISIBLE_DEVICES=all
 ENV NVIDIA_DRIVER_CAPABILITIES=utility