java.lang.NullPointerException: null

Monitor initialization fails with below exception.
Please advise on the fix

```
[Agent-Monitor-Scheduler-1] 11 Aug 2022 18:28:51,220 ERROR SQLMonitor - Error while creating task for dbServer
java.lang.NullPointerException: null
at com.appdynamics.extensions.sql.SQLMonitor.getConnectionProperties(SQLMonitor.java:113) ~[?:?]
at com.appdynamics.extensions.sql.SQLMonitor.createTask(SQLMonitor.java:81) ~[?:?]
at com.appdynamics.extensions.sql.SQLMonitor.doRun(SQLMonitor.java:49) [?:?]
at com.appdynamics.extensions.AMonitorJob.run(AMonitorJob.java:50) [?:?]
at com.appdynamics.extensions.ABaseMonitor.executeMonitor(ABaseMonitor.java:199) [?:?]
at com.appdynamics.extensions.ABaseMonitor.execute(ABaseMonitor.java:187) [?:?]
at com.singularity.ee.agent.systemagent.components.monitormanager.managed.MonitorTaskRunner.runTask(MonitorTaskRunner.java:149) [machineagent.jar:Machine Agent v21.12.6-3236 GA compatible with 4.4.1.0 Build Date 2022-01-15 06:37:49]
at com.singularity.ee.agent.systemagent.components.monitormanager.managed.PeriodicTaskRunner.runTask(PeriodicTaskRunner.java:86) [machineagent.jar:Machine Agent v21.12.6-3236 GA compatible with 4.4.1.0 Build Date 2022-01-15 06:37:49]
at com.singularity.ee.agent.systemagent.components.monitormanager.managed.PeriodicTaskRunner.run(PeriodicTaskRunner.java:47) [machineagent.jar:Machine Agent v21.12.6-3236 GA compatible with 4.4.1.0 Build Date 2022-01-15 06:37:49]
at com.singularity.ee.util.javaspecific.scheduler.AgentScheduledExecutorServiceImpl$SafeRunnable.run(AgentScheduledExecutorServiceImpl.java:122) [agent-21.1.0-2340.jar:?]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_292]
at com.singularity.ee.util.javaspecific.scheduler.ADFutureTask$Sync.innerRunAndReset(ADFutureTask.java:335) [agent-21.1.0-2340.jar:?]
at com.singularity.ee.util.javaspecific.scheduler.ADFutureTask.runAndReset(ADFutureTask.java:152) [agent-21.1.0-2340.jar:?]
at com.singularity.ee.util.javaspecific.scheduler.ADScheduledThreadPoolExecutor$ADScheduledFutureTask.access$101(ADScheduledThreadPoolExecutor.java:119) [agent-21.1.0-2340.jar:?]
at com.singularity.ee.util.javaspecific.scheduler.ADScheduledThreadPoolExecutor$ADScheduledFutureTask.runPeriodic(ADScheduledThreadPoolExecutor.java:206) [agent-21.1.0-2340.jar:?]
at com.singularity.ee.util.javaspecific.scheduler.ADScheduledThreadPoolExecutor$ADScheduledFutureTask.run(ADScheduledThreadPoolExecutor.java:236) [agent-21.1.0-2340.jar:?]
at com.singularity.ee.util.javaspecific.scheduler.ADThreadPoolExecutor$Worker.runTask(ADThreadPoolExecutor.java:694) [agent-21.1.0-2340.jar:?]
at com.singularity.ee.util.javaspecific.scheduler.ADThreadPoolExecutor$Worker.run(ADThreadPoolExecutor.java:726) [agent-21.1.0-2340.jar:?]
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_292]

```

从 SQLMonitor.java 中的 getConnectionProperties(SQLMonitor.java:113) 开始，然后使用提供的初始化堆栈跟踪跟进第 81 行的 createTask 和第 49 行的 doRun。确定哪个配置值或连接值为 null，并验证 monitor 初始化能够在不出现此异常的情况下完成；issue 中未指定测试或复现设置。

由索引模型根据 Issue 内容生成。