update images with public cr

[paradiseHIT]

update images with public cr
mybigpai-registry.cn-beijing.cr.aliyuncs.com/easyrec/easyrec:py36-tf1.15-0.6.3
to
mybigpai-public-registry.cn-beijing.cr.aliyuncs.com/easyrec/easyrec:py36-tf1.15-0.7.4

[CLAassistant]

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[github-actions]

Code Style Test Passed