KT-53146 Don't coerce Nothing? returned from "catch" clauses

At first, I tried to modify the logic in PromisedValue.materializeAt
to get rid of all casts from Nothing? to other types, but that broke
a number of tests containing casts of java.lang.Void to other types,
so I decided to fix only this particular case with try...catch
(for some reason, here we get a null of type java.lang.Object).

compiler/ir/backend.jvm/codegen/src/org/jetbrains/kotlin/backend/jvm/codegen/ExpressionCodegen.kt

@@ -1225,7 +1225,9 @@ class ExpressionCodegen(
 
             val catchResult = catchBody.accept(this, catchBlockInfo)
             if (savedValue != null) {
-                catchResult.materializeAt(tryAsmType, aTry.type, true)
+                if (catchResult.irType != context.irBuiltIns.nothingNType) {
+                    catchResult.materializeAt(tryAsmType, aTry.type, true)
+                }
                 mv.store(savedValue, tryAsmType)
             } else {
                 catchResult.discard()