[Feature] Move the dockerImage from the service properties to the configuration options.

[linshenkx]

Is your feature request related to a problem? Please describe.
一个服务可能有多个镜像，比方说一个init镜像，一个应用镜像，一个exporter，一个filebeat之类。
或者不同服务用的镜像可能也不一样。
当前只能配置一个，且除了用于提前拉取，没有其他实际用途。
【dockerImage】没有作为组件属性的必要，应作为配置项处理。

Describe the solution you'd like
将【dockerImage】放到conf配置项里面

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.