mapToJvmSignature crash on local class

Given this top-level function and local class:

```
private fun simple() {
class VerySimple
}
```

Calling `Resolver.mapToJvmSignature()` on the `KSClassDeclaration` corresponding to `class VerySimple` crashes ksp:

```
java.lang.IllegalArgumentException: Unexpected container: private fun simple(): kotlin.Unit defined in com.example in file Sample.kt[SimpleFunctionDescriptorImpl@6668c51f] for class VerySimple
at org.jetbrains.kotlin.load.kotlin.DescriptorBasedTypeSignatureMappingKt.computeInternalName(descriptorBasedTypeSignatureMapping.kt:190)
at org.jetbrains.kotlin.load.kotlin.DescriptorBasedTypeSignatureMappingKt.mapType(descriptorBasedTypeSignatureMapping.kt:141)
at org.jetbrains.kotlin.codegen.state.KotlinTypeMapper.mapType(KotlinTypeMapper.kt:276)
at org.jetbrains.kotlin.codegen.state.KotlinTypeMapper.mapType$default(KotlinTypeMapper.kt:267)
at org.jetbrains.kotlin.codegen.state.KotlinTypeMapper.mapType(KotlinTypeMapper.kt:263)
at com.google.devtools.ksp.processing.impl.ResolverImpl.mapToJvmSignatureInternal$compiler_plugin(ResolverImpl.kt:356)
at com.google.devtools.ksp.processing.impl.ResolverImpl.mapToJvmSignature(ResolverImpl.kt:353)
at org.bubenheimer.instancelimit.InstanceLimitProcessor.createClassInfo(InstanceLimitProcessor.kt:111)
at org.bubenheimer.instancelimit.InstanceLimitProcessor.addInstanceLimit(InstanceLimitProcessor.kt:64)
at org.bubenheimer.instancelimit.InstanceLimitProcessor.process(InstanceLimitProcessor.kt:214)
at org.bubenheimer.instancelimit.InstanceLimitProcessor.process(InstanceLimitProcessor.kt:140)
at com.google.devtools.ksp.AbstractKotlinSymbolProcessingExtension$doAnalysis$6$1.invoke(KotlinSymbolProcessingExtension.kt:291)
at com.google.devtools.ksp.AbstractKotlinSymbolProcessingExtension$doAnalysis$6$1.invoke(KotlinSymbolProcessingExtension.kt:289)
at com.google.devtools.ksp.AbstractKotlinSymbolProcessingExtension.handleException(KotlinSymbolProcessingExtension.kt:394)
at com.google.devtools.ksp.AbstractKotlinSymbolProcessingExtension.doAnalysis(KotlinSymbolProcessingExtension.kt:289)
at org.jetbrains.kotlin.cli.jvm.compiler.TopDownAnalyzerFacadeForJVM.analyzeFilesWithJavaIntegration(TopDownAnalyzerFacadeForJVM.kt:123)
at org.jetbrains.kotlin.cli.jvm.compiler.TopDownAnalyzerFacadeForJVM.analyzeFilesWithJavaIntegration$default(TopDownAnalyzerFacadeForJVM.kt:99)
at org.jetbrains.kotlin.cli.jvm.compiler.KotlinToJVMBytecodeCompiler$analyze$1.invoke(KotlinToJVMBytecodeCompiler.kt:257)
at org.jetbrains.kotlin.cli.jvm.compiler.KotlinToJVMBytecodeCompiler$analyze$1.invoke(KotlinToJVMBytecodeCompiler.kt:42)
at org.jetbrains.kotlin.cli.common.messages.AnalyzerWithCompilerReport.analyzeAndReport(AnalyzerWithCompilerReport.kt:115)
at org.jetbrains.kotlin.cli.jvm.compiler.KotlinToJVMBytecodeCompiler.analyze(KotlinToJVMBytecodeCompiler.kt:248)
at org.jetbrains.kotlin.cli.jvm.compiler.KotlinToJVMBytecodeCompiler.compileModules$cli(KotlinToJVMBytecodeCompiler.kt:88)
at org.jetbrains.kotlin.cli.jvm.compiler.KotlinToJVMBytecodeCompiler.compileModules$cli$default(KotlinToJVMBytecodeCompiler.kt:47)
at org.jetbrains.kotlin.cli.jvm.K2JVMCompiler.doExecute(K2JVMCompiler.kt:167)
at org.jetbrains.kotlin.cli.jvm.K2JVMCompiler.doExecute(K2JVMCompiler.kt:53)
at org.jetbrains.kotlin.cli.common.CLICompiler.execImpl(CLICompiler.kt:101)
at org.jetbrains.kotlin.cli.common.CLICompiler.execImpl(CLICompiler.kt:47)
at org.jetbrains.kotlin.cli.common.CLITool.exec(CLITool.kt:101)
at org.jetbrains.kotlin.daemon.CompileServiceImpl.compile(CompileServiceImpl.kt:1645)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.base/java.lang.reflect.Method.invoke(Unknown Source)
at java.rmi/sun.rmi.server.UnicastServerRef.dispatch(Unknown Source)
at java.rmi/sun.rmi.transport.Transport$1.run(Unknown Source)
```

I got this on the `1.0.10-release` branch, guessing it's not specific to just that branch.