[FIX]:add flink command line doc

[xxsc0529]

Summary

Documentation for the Flink Command Line to added. close #111

Solution Description

Added documentation in English and Chinese and supplemented some tests
flink-connector-oceanbase-tools-cdc/src/test/java/com/oceanbase/cdc/tools/tests/tools/DatabaseSyncTest.java
docs/sink/flink-connector-oceanbase-tools-cdc_cn.md
docs/sink/flink-connector-oceanbase-tools-cdc.md

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✅ xxsc0529
❌ zyh

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