Bump devcontainer OS version

Author: spenserblack

.devcontainer/Dockerfile

@@ -1,3 +1,3 @@
-ARG VARIANT="buster"
+ARG VARIANT="bookworm"
 FROM mcr.microsoft.com/devcontainers/rust:1-${VARIANT}
 RUN sudo apt update && sudo apt install -y cmake

.devcontainer/devcontainer.json

@@ -2,7 +2,7 @@
   "name": "Rust",
   "build": {
     "dockerfile": "Dockerfile",
-    "args": { "VARIANT": "buster" }
+    "args": { "VARIANT": "bookworm" }
   },
   "postCreateCommand": "git config --global --add safe.directory $PWD && cargo install cargo-insta",
   "extensions": ["EditorConfig.EditorConfig"],