Android使用dokit插件，编译报错KotlinNullPointerException

1. dokit版本：
debugImplementation "com.didichuxing.doraemonkit:dokitx:3.3.5"
releaseImplementation "com.didichuxing.doraemonkit:dokitx-no-op:3.3.5"
classpath 'com.didichuxing.doraemonkit:dokitx-plugin:3.3.5'

2. 项目gralde版本：
classpath "com.android.tools.build:gradle:4.0.1"
buildToolsVersion 29.0.3
distributionUrl=https\://services.gradle.org/distributions/gradle-6.1.1-all.zip

3. 问题描述
使用 apply plugin: 'com.didi.dokit'时，项目编译报错：
`Caused by: kotlin.KotlinNullPointerException
at com.didichuxing.doraemonkit.plugin.processor.DoKitPluginConfigProcessor.process(DoKitPluginConfigProcessor.kt:69)
at com.didichuxing.doraemonkit.plugin.DoKitPlugin$apply$1$1.execute(DoKitPlugin.kt:123)
at com.didichuxing.doraemonkit.plugin.DoKitPlugin$apply$1$1.execute(DoKitPlugin.kt:28)
at org.gradle.configuration.internal.DefaultListenerBuildOperationDecorator$BuildOperationEmittingAction$1.lambda$run$0(DefaultListenerBuildOperationDecorator.java:152)
at org.gradle.configuration.internal.DefaultUserCodeApplicationContext.reapply(DefaultUserCodeApplicationContext.java:60)
at org.gradle.configuration.internal.DefaultListenerBuildOperationDecorator$BuildOperationEmittingAction$1.run(DefaultListenerBuildOperationDecorator.java:152)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:402)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:394)
at org.gradle.internal.operations.DefaultBuildOperationExecutor$1.execute(DefaultBuildOperationExecutor.java:165)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:250)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:158)
at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:92)
at org.gradle.configuration.internal.DefaultListenerBuildOperationDecorator$BuildOperationEmittingAction.execute(DefaultListenerBuildOperationDecorator.java:149)
at org.gradle.internal.event.BroadcastDispatch$ActionInvocationHandler.dispatch(BroadcastDispatch.java:92)
at org.gradle.internal.event.BroadcastDispatch$ActionInvocationHandler.dispatch(BroadcastDispatch.java:80)
at org.gradle.internal.event.AbstractBroadcastDispatch.dispatch(AbstractBroadcastDispatch.java:42)
at org.gradle.internal.event.BroadcastDispatch$SingletonDispatch.dispatch(BroadcastDispatch.java:231)
at org.gradle.internal.event.BroadcastDispatch$SingletonDispatch.dispatch(BroadcastDispatch.java:150)
at org.gradle.internal.event.AbstractBroadcastDispatch.dispatch(AbstractBroadcastDispatch.java:58)
at org.gradle.internal.event.BroadcastDispatch$CompositeDispatch.dispatch(BroadcastDispatch.java:325)
at org.gradle.internal.event.BroadcastDispatch$CompositeDispatch.dispatch(BroadcastDispatch.java:235)
at org.gradle.internal.event.ListenerBroadcast.dispatch(ListenerBroadcast.java:141)
at org.gradle.internal.event.ListenerBroadcast.dispatch(ListenerBroadcast.java:37)
at org.gradle.internal.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:94)
at com.sun.proxy.$Proxy29.afterEvaluate(Unknown Source)
at org.gradle.configuration.project.LifecycleProjectEvaluator$NotifyAfterEvaluate$1.execute(LifecycleProjectEvaluator.java:191)
at org.gradle.configuration.project.LifecycleProjectEvaluator$NotifyAfterEvaluate$1.execute(LifecycleProjectEvaluator.java:188)
at org.gradle.api.internal.project.DefaultProject.stepEvaluationListener(DefaultProject.java:1434)
at org.gradle.configuration.project.LifecycleProjectEvaluator$NotifyAfterEvaluate.run(LifecycleProjectEvaluator.java:197)
... 115 more`