feat():canal-adapter同步到rdb时，mirrorDb模式下支持改库名

[sgjr]

• 使用场景为：MySQL同步数据到MySQL，下游MySQL实例中的库名需要修改， 相关issue: MySQL同步到MySQL修改库名，canal-adapter如何配置dbMapping #5216
• 当 dbMapping 中 mirrorDb 为 true时，支持通过设置 targetDb 来进行改库名操作
• rdb配置实例如下

concurrent: true
dataSourceKey: demoSyncDS
dbMapping:
  commitBatch: 3000
  database: test0718
  mirrorDb: true
  targetDb: test0723
destination: demo-1721045534
groupId: g1
outerAdapterKey: mysql0

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