chore(devcontainer): add docker volume for node_modules

Signed-off-by: Xe Iaso <me@xeiaso.net>

Author: Xe

.devcontainer/Dockerfile

@@ -3,4 +3,6 @@ FROM ghcr.io/xe/devcontainer-base/pre/go
 RUN apt update \
   && apt -y install redis postgresql-client
 
-CMD ["/usr/bin/sleep", "infinity"]
+CMD ["/usr/bin/sleep", "infinity"]
+
+VOLUME /workspace/alexandria/node_modules