当我使用混淆方法Generate Signed APK（minifyEnabled true shrinkResources true）时，会报错。错误信息如下。但当不混淆时（minifyEnabled false shrinkResources false），就成功了。
Missing classes detected while running R8. Please add the missing classes or apply additional keep rules that are generated in ...\missing_rules.txt.
Missing class java.lang.management.ManagementFactory (referenced from: long org.junit.internal.runners.statements.FailOnTimeout.cpuTime(java.lang.Thread) and 1 other context)
Missing class java.lang.management.RuntimeMXBean (referenced from: void org.junit.rules.DisableOnDebug.<init>(org.junit.rules.TestRule))
Missing class java.lang.management.ThreadMXBean (referenced from: long org.junit.internal.runners.statements.FailOnTimeout.cpuTime(java.lang.Thread))
我需要使用混淆成功生成签名的 APK。我能做些什么？