Add junit5 test code for module [linkis-engineconn-manager-server]

[ruY9527]

Add junit5 test code for module [linkis-engineconn-manager-server]

• Module: linkis-engineconn-manager-server
• Location: linkis-computation-governance/linkis-engineconn-manager-server
• Task status:✗(unfinished)/ ✓(finished)
• Test code guide:https://linkis.apache.org/zh-CN/community/how-to-write-unit-test-code/
• Test code example: https://github.com/apache/incubator-linkis/tree/master/linkis-public-enhancements/linkis-publicservice/linkis-jobhistory/src/test --
• 模块名: linkis-engineconn-manager-server
• 代码位置: linkis-computation-governance/linkis-engineconn-manager-server
• 任务状态:✗(unfinished)/ ✓(finished)
• 单测编写指引:https://linkis.apache.org/zh-CN/community/how-to-write-unit-test-code/
• 参考样例: https://github.com/apache/incubator-linkis/tree/master/linkis-public-enhancements/linkis-publicservice/linkis-jobhistory/src/test

Task status	Class	Type	Level of Difficulty	Note
✗	org.apache.linkis.ecm.server.converter.ECMEngineConverter	Converter	normal
✗	org.apache.linkis.ecm.server.exception.ECMErrorException	Exception	normal
✗	org.apache.linkis.ecm.server.hook.JarUDFLoadECMHook	Hook	normal
✗	org.apache.linkis.ecm.server.metrics.DefaultECMMetrics	Metrics	normal
✗	org.apache.linkis.ecm.server.operator.*	Operator	normal
✗	org.apache.linkis.ecm.server.service.impl.*	Service	normal
✗	org.apache.linkis.ecm.server.util.*	Utils	normal