fix(devcontainer): try adjusting scripts/setup for xdebug VSCode extension

.devcontainer/postCreateCommand.sh

@@ -5,7 +5,7 @@ export PATH="$PATH:$PWD/vendor/bin"
 echo 'export PATH="$PATH:$HOME/.composer/vendor/bin"' >> ~/.bashrc
 echo 'export PATH="$PATH:$PWD/vendor/bin"' >> ~/.bashrc
 ln -s ./conf.sample.php cfg/conf.php
-composer install --no-dev --optimize-autoloader
+composer install --optimize-autoloader
 
 # for PHP unit testing
 composer require --global google/cloud-storage

.vscode/settings.json

@@ -1,5 +1,9 @@
 {
     "files.associations": {
         "**/cfg/conf*.php": "ini"
-    }
+    },
+    "phpunit.phpunit": "${workspaceFolder}/vendor/bin/phpunit",
+    "phpunit.args": [
+        "--configuration '${workspaceFolder}/tst/phpunit.xml'"
+    ]
 }