Further devcontainer updates

- Bump postgresql image from 13 to 15
- Store psql data in the dev/psql directory
- Install required frontend packages

.devcontainer/Dockerfile

@@ -12,8 +12,7 @@ ENV INVENTREE_STATIC_ROOT="${INVENTREE_DATA_DIR}/static"
 ENV INVENTREE_MEDIA_ROOT="${INVENTREE_DATA_DIR}/media"
 ENV INVENTREE_BACKUP_DIR="${INVENTREE_DATA_DIR}/backup"
 ENV INVENTREE_PLUGIN_DIR="${INVENTREE_DATA_DIR}/plugins"
-
-ENV INVENTREE_DOCKER="true"
+ENV INVENTREE_CONFIG_FILE="${INVENTREE_DATA_DIR}/config.yaml"
 
 COPY contrib/container/init.sh ./
 RUN chmod +x init.sh
@@ -26,6 +25,12 @@ RUN apt update && apt install -y \
    libpango1.0-0 libcairo2 \
    weasyprint
 
+# Install packages required for frontend development
+RUN apt install -y \
+   yarn nodejs npm
+
+RUN yarn config set network-timeout 600000 -g
+
 # Install python database connectors
 
 ENTRYPOINT ["/bin/bash", "./init.sh"]