[Bug]: Allow drop non-empty external catalogs

[link3280]

Search before asking

• [X] I have searched in the issues and found no similar issues.

What would you like to be improved?

Currently, it's forbidden to remove a non-empty catalog if a catalog has managed tables. However, the implementation actually checks all tables, not only the managed ones. As a result, external catalogs can never be removed.

https://github.com/apache/amoro/blob/84e095b6e28a1730d2709daedf0acbffad7b12fc/ams/server/src/main/java/com/netease/arctic/server/table/DefaultTableService.java#L233-L237

How should we improve?

No response

Are you willing to submit PR?

• [X] Yes I am willing to submit a PR!

Subtasks

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Code of Conduct

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