[Improve][Manager] Fix SSRF in DataNode testConnection

[fuweng11]

Description

POST /api/node/testConnection is vulnerable to SSRF. DataNodeServiceImpl.testConnection only validates DataNodeRequest.url via UrlVerificationUtils.validateUrlNotInternal, but each operator connects using its own field, which is never validated.

InLong Component

InLong Manager

Are you willing to submit PR?

• Yes, I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct