fix dockerfile so it can build successfully

Author: Jian Gao

src/auth/Dockerfile

@@ -2,7 +2,7 @@ FROM python:3.10-slim-bullseye
 
 RUN apt-get update \
   && apt-get install -y --no-install-recommends --no-install-suggests \
-  build-essential default-libmysqlclient-dev \
+  build-essential default-libmysqlclient-dev pkg-config \
   && pip install --no-cache-dir --upgrade pip
 
 WORKDIR /app