[Bug] [api][runtime] Call from_datastream and then to_table will cause exception.

[wenjin272]

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• I searched in the issues and found nothing similar.

Description

Currently, when user call from_datastream and then to_table when build an flink job with agent, it will throw exception for table env is null.

How to reproduce

agent_env.from_datastream(input_stream).apply(agent).to_table()

Version and environment

all versions

Are you willing to submit a PR?

• I'm willing to submit a PR!