Fix dockerfile

Dockerfile

@@ -27,6 +27,12 @@ ENV WHITELIST_USERS  ''
 
 WORKDIR /app
 
+RUN apt-get update && \
+    apt-get install -y --no-install-recommends \
+        build-essential && \
+    apt-get clean && \
+    rm -rf /var/lib/apt/lists/*
+
 COPY ./requirements.txt ./
 RUN pip install --no-cache-dir -r requirements.txt