Add $completion entry to suspend functions' LVT

#KT-28810 Fixed

compiler/testData/checkLocalVariablesTable/completionInSuspendFunction/staticSimpleReceiver.kt

@@ -0,0 +1,10 @@
+// IGNORE_BACKEND: JVM_IR
+// WITH_RUNTIME
+
+class A
+
+suspend fun A.foo() {}
+
+// METHOD : StaticSimpleReceiverKt.foo(LA;Lkotlin/coroutines/Continuation;)Ljava/lang/Object;
+// VARIABLE : NAME=$receiver TYPE=LA; INDEX=0
+// VARIABLE : NAME=$completion TYPE=Lkotlin/coroutines/Continuation; INDEX=1