Add junit5 test code for module [linkis-gateway-core]

### Add junit5 test code for module [linkis-gateway-core]
- Module: linkis-gateway-core
- Location:linkis-spring-cloud-services/linkis-gateway-core
- 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-gateway-core
- 代码位置:linkis-spring-cloud-services/linkis-gateway-core
- 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.gateway.config.*| config | normal | |
| ✗ |org.apache.linkis.gateway.exception.*| exception | normal | |
| ✗ |org.apache.linkis.gateway.parser.GatewayParser| parser | normal | |
| ✗ |org.apache.linkis.gateway.route.GatewayRouter| router | normal | |
| ✗ |org.apache.linkis.gateway.security.GatewaySSOUtils| utils | normal | |
| ✗ |org.apache.linkis.gateway.security.LDAPUserRestful| api | normal | |
| ✗ |org.apache.linkis.gateway.security.ProxyUserUtils| utils | normal | |
| ✗ |org.apache.linkis.gateway.security.UserRestful| api | normal | |
| ✗ |org.apache.linkis.rpc.interceptor.ServiceInstanceUtils| utils | normal | |
| ✗ |org.apache.linkis.server.security.ServerSSOUtils| utils | normal | |