What is the best way to share maven repository using Docker build (dynamic) image with maven?
You might use docker builder pattern. Briefly you need to create Dockerfile.build which adds pom.xml and run mvn dependency:resolve:

FROM maven:latest
ADD ./pom.xml /src/pom.xml
WORKDIR /src
RUN mvn dependency:resolve


Rebuild that image every time prior build. Docker will use cached image if ./pom.xml has not changed. 

Docker 17.05 introduced 'multi-stage builds' feature which implements this pattern. More information is available here: https://docs.docker.com/engine/userguide/eng-image/multistage-build/