Remove unneeded packages and environment variables from the builder

Dockerfile.tomcat

@@ -1,13 +1,8 @@
 FROM maven:3-jdk-8 AS builder
 
-RUN apt-get update && \
-    apt-get install -y --no-install-recommends graphviz fonts-wqy-zenhei && \
-    apt-get clean
-
 COPY pom.xml /app/
 COPY src /app/src/
 
-ENV MAVEN_CONFIG=/app/.m2
 WORKDIR /app
 RUN mvn package