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• I have checked the FAQ of this repository and believe that this is not a duplicate.

environment

• canal version 1.1.5
• mysql 8.0.25
• es7.12 跟 es6.8

Issue Description

es配置文件配置正确后，启动adapter就会报错。不配置es文件的时候，是可以正常启动的，或者es文件配置错误时，会提示es文件的错误。es6跟es7报一样的错。
java.lang.RuntimeException: java.lang.ClassCastException: com.alibaba.druid.pool.DruidDataSource cannot be cast to com.alibaba.druid.pool.DruidDataSource

If there is an exception, please attach the exception trace:

2021-05-20 17:52:58.189 [main] INFO  c.a.o.c.client.adapter.es.core.config.ESSyncConfigLoader - ## ES mapping config loaded
2021-05-20 17:52:58.595 [main] ERROR c.a.o.canal.adapter.launcher.loader.CanalAdapterLoader - Load canal adapter: es6 failed
java.lang.RuntimeException: java.lang.RuntimeException: java.lang.ClassCastException: com.alibaba.druid.pool.DruidDataSource cannot be cast to com.alibaba.druid.pool.DruidDataSource
        at com.alibaba.otter.canal.client.adapter.es6x.ES6xAdapter.init(ES6xAdapter.java:54) ~[client-adapter.es6x-1.1.5-jar-with-dependencies.jar:na]
        at com.alibaba.otter.canal.adapter.launcher.loader.CanalAdapterLoader.loadAdapter(CanalAdapterLoader.java:225) [client-adapter.launcher-1.1.5.jar:na]
        at com.alibaba.otter.canal.adapter.launcher.loader.CanalAdapterLoader.init(CanalAdapterLoader.java:56) [client-adapter.launcher-1.1.5.jar:na]
        at com.alibaba.otter.canal.adapter.launcher.loader.CanalAdapterService.init(CanalAdapterService.java:60) [client-adapter.launcher-1.1.5.jar:na]
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_292]
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_292]
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_292]
        at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_292]
        at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleElement.invoke(InitDestroyAnnotationBeanPostProcessor.java:365) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
        at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleMetadata.invokeInitMethods(InitDestroyAnnotationBeanPostProcessor.java:308) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
        at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessBeforeInitialization(InitDestroyAnnotationBeanPostProcessor.java:135) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyBeanPostProcessorsBeforeInitialization(AbstractAutowireCapableBeanFactory.java:422) [spring-beans-5.0.5.RELEASE.jar:5.0.5.RELEASE]