Fix heat-container-agent image building error on arm64
Fix heat-container-agent image building error on arm64

Fix bellow building error on arm64.
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  build/temp.linux-aarch64-3.8/_openssl.c:498:10: fatal error: openssl/opensslv.h: No such file or directory
    498 | #include <openssl/opensslv.h>
        |          ^~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  error: command 'gcc' failed with exit status 1
  ----------------------------------------
  ERROR: Failed building wheel for cryptography
  Running setup.py clean for cryptography
  Failed to build cryptography
  ERROR: Could not build wheels for cryptography
  which use PEP 517 and cannot be installed directly
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Additionally, add an ARCH ARG to pass other architecure value when
building image.
E.g: $ docker build --build-arg ARCH=`uname -m` -t TAGNAME .

task: 37823
story: 2007026

Change-Id: I7f62b882fa812beb74e38bbc5916d9df5afbd481

ArchiFleKs/magnum,openstack/magnum,openstack/magnum,ArchiFleKs/magnum