Update Dockerfile

backend/Dockerfile

@@ -5,10 +5,11 @@ ENV PYTHONDONTWRITEBYTECODE=1 \
 
 WORKDIR /app
 
-# deps for psycopg2
+# deps for psycopg2 and pg_dump/psql for backups
 RUN apt-get update && apt-get install -y --no-install-recommends \
     build-essential \
     libpq-dev \
+    postgresql-client \
   && rm -rf /var/lib/apt/lists/*
 
 COPY requirements.txt .