[Spring-Cloud] refactor spring-cloud create

[yuwzho]

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This PR refactors the logic in az spring-cloud create. In previous implementation, it was major implemented by if/else switches. If Enterprise goes to one place else to another.
This change uses template to divide the creation into before/creating/after phases. Every tier implementations can define its own steps.

This PR will bumb up versions with other PRs together in #4294

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[yonzhan]

Spring-Cloud