Add prompt prefix to devcontainers (#14)

This is used by my dotfiles to replace user@host (which is a bit
pointless in devcontainers).

Author: csutter

src/personal-setup/devcontainer-feature.json

@@ -1,6 +1,6 @@
 {
   "id": "personal-setup",
-  "version": "4.0.0",
+  "version": "4.1.0",
   "name": "Personal Setup",
   "description": "Sets up my desired software and configuration for any devcontainer environment.",
   "mounts": [
@@ -17,6 +17,7 @@
   ],
   "containerEnv": {
     "RCRC": "/mnt/dotfiles/tag-devcontainer/rcrc",
+    "PROMPT_PREFIX": "", // Nerd font "remote" icon
     "_IS_DEVCONTAINER": "true"
   },
   "postCreateCommand": "rcup -vf"

test/personal-setup/test.sh

@@ -11,5 +11,6 @@ check "tree is available"       bash -c "which tree"
 # Use a dotfile that should _always_ be present on any system
 check "dotfiles are installed"  bash -c "test -f $HOME/.rcrc"
 check "_IS_DEVCONTAINER is set" bash -c "test \"\$_IS_DEVCONTAINER\" = \"true\""
+check "PROMPT_PREFIX is set"    bash -c "test \"\$PROMPT_PREFIX\" = \"\""
 
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