fix NullPointerException for Kotlin typealias of typealias of lambda

[huqiuser]

fix #309
If the kotlin version is lower than v2.0.0, such as 1.9.0, the following code can reproduce the problem

package com.hello

import androidx.annotation.Keep

typealias typeOne = () -> Unit
typealias typeTwo = typeOne

class KotlinQQ {
    @Keep
    fun testWorld(world: typeTwo) {
    }
}

[rubenpieters]

Hey! Thanks for creating your PR. Would it be possible for you to add the test case you mentioned in the test cases here: https://github.com/Guardsquare/proguard/blob/master/base/src/test/kotlin/proguard/shrink/ClassUsageMarkerTest.kt ? That way this will make it easier for us to understand the issue you ran into, and confirm the fix for the problem.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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