message: Remove even more of cargo registry
diff: @@ -7,8 +7,7 @@ COPY . /opt/tarpaulin/
  RUN cd /opt/tarpaulin/ && \
  cargo install && \
  rm -rf /opt/tarpaulin/ && \
  - rm -rf /usr/local/cargo/registry/cache/ && \
  - rm -rf /usr/local/cargo/registry/src/
  + rm -rf /usr/local/cargo/registry/
  WORKDIR /volume
  