Reduce image size (#4132)
Reduce image size (#4132)

* Reduce Dockerfile size
1. del redis stage
2. del flink stage
3. del conda & exclude some python packages
4. add copies layer stage

* update numpy version to 1.18.1

Co-authored-by: zzti-bsj <cd9162835afa154941a3d7d99d801a528eb1bd22@intel.com>
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