Update Dockerfile

Dockerfile

@@ -7,7 +7,7 @@ ARG INSTALL_SCRIPT=https://raw.githubusercontent.com/fithwum/minecraft/master/fi
 # Install java8 & dependencies.
 RUN apt-get update && apt-get install libstdc++ software-properties-common \
 	&& apt-get install -y openjdk-8-jdk \
-	&& apt-get clean && rm -rf /var/lib/apt/lists/*
+	&& apt-get clean && rm -rf /var/lib/apt/lists/* \
 	&& apt-get install ca-certificates-java \
 	&& apt-get clean \
 	&& update-ca-certificates -f;