[Optimization] Move spring compatibility tests to the dubbo-Integration-case project

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### Apache Dubbo Component

Java SDK (apache/dubbo)

### Descriptions

We must ensure that the Dubbo core project only has unit tests.

### Related issues

_No response_

### Are you willing to submit a pull request to fix on your own?

- [ ] Yes I am willing to submit a pull request on my own!

### Code of Conduct

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The issue identifies Spring compatibility tests and the dubbo-Integration-case project but names no files or test entry points. Locate the Spring compatibility tests and inspect how the target project organizes and runs them. Done means the Dubbo core project contains only unit tests and the moved compatibility tests run from dubbo-Integration-case.

Written by the indexing model from the issue text.