Try to remove everything in one go

Dockerfile

@@ -39,7 +39,7 @@ RUN npm -g install Haraka \
 
 USER root
 
-RUN apt-get -y remove git && apt-get autoremove && \
+RUN apt-get -y autoremove git \
     rm -rf /var/lib/apt/lists/*
 
 # Port 80 is used for LetsEncrypt