Devcontainer: use "batman" user instead of root (#29704)

* devcontainer user

* cleanup permissions

* remove that

* remove that since it's not used

* clean that up after merge

* build base image first

* remove the pull

* build base image

* ensure we can pip install

* build base image as batman user

* add user uid

* add temporary comment about chown instruction
old-commit-hash: 021effc5ac

.devcontainer/devcontainer.json

@@ -14,13 +14,23 @@
   },
   "runArgs": [
     "--volume=/tmp/.X11-unix:/tmp/.X11-unix",
-    "--volume=${localWorkspaceFolder}/.devcontainer/.host/.Xauthority:/root/.Xauthority",
-    "--volume=${localEnv:HOME}/.comma:/root/.comma",
+    "--volume=${localWorkspaceFolder}/.devcontainer/.host/.Xauthority:/home/batman/.Xauthority",
+    "--volume=${localEnv:HOME}/.comma:/home/batman/.comma",
     "--volume=/tmp/comma_download_cache:/tmp/comma_download_cache",
     "--volume=/tmp/devcontainer_scons_cache:/tmp/scons_cache",
     "--shm-size=1G",
     "--add-host=host.docker.internal:host-gateway" // required to use host.docker.internal on linux
   ],
+  "features": {
+    "ghcr.io/devcontainers/features/common-utils:2": {
+      "installZsh": false,
+      "installOhMyZsh": false,
+      "upgradePackages": false,
+      "username": "batman"
+    }
+  },
+  "containerUser": "root",
+  "remoteUser": "batman",
   "customizations": {
     "vscode": {
       "extensions": [