add connection timeout

[dh-cloud]

Description

when we use export csv tool，found export command can not return, locate discovery socket timeout not set，socket timeout is equal to connection timeout

Content1 ...

default connection timeout is 0， timeout of zero is interpreted as infinit timeout。 may cause connection hang or query hang

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This PR has:

• [x] been self-reviewed.
  • [ ] concurrent read
  • [ ] concurrent write
  • [ ] concurrent read and write
• [ ] added documentation for new or modified features or behaviors.
• [ ] added Javadocs for most classes and all non-trivial methods.
• [ ] added or updated version, license, or notice information
• [ ] added comments explaining the "why" and the intent of the code wherever would not be obvious for an unfamiliar reader.
• [ ] added unit tests or modified existing tests to cover new code paths, ensuring the threshold for code coverage.
• [ ] added integration tests.
• [ ] been tested in a test IoTDB cluster.

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Key changed/added classes (or packages if there are too many classes) in this PR