[Test] Save IR bytecode dumps from BytecodeListingHandler to .ir.txt file instead of _ir.txt

This is needed to keep consistency with other dumps and to allow
  test helper plugin to recognize those dumps

compiler/testData/codegen/bytecodeListing/delegatedProperty/delegateMethodIsNonOverridable.ir.txt

@@ -0,0 +1,53 @@
+@kotlin.Metadata
+synthetic final class C$x$2$1 {
+    // source: 'delegateMethodIsNonOverridable.kt'
+    enclosing method C.<init>()V
+    public final static field INSTANCE: C$x$2$1
+    inner (anonymous) class C$x$2$1
+    static method <clinit>(): void
+    method <init>(): void
+    public @org.jetbrains.annotations.Nullable method get(): java.lang.Object
+}
+
+@kotlin.Metadata
+public class C {
+    // source: 'delegateMethodIsNonOverridable.kt'
+    private final @org.jetbrains.annotations.NotNull field x$delegate: kotlin.reflect.KProperty0
+    inner (anonymous) class C$x$2$1
+    public method <init>(): void
+    public method getX(): int
+    private static method getY$delegate(p0: C): java.lang.Object
+    public method getY(): int
+}
+
+@kotlin.Metadata
+synthetic final class D$x$2$1 {
+    // source: 'delegateMethodIsNonOverridable.kt'
+    enclosing method D.<init>()V
+    public final static field INSTANCE: D$x$2$1
+    inner (anonymous) class D$x$2$1
+    static method <clinit>(): void
+    method <init>(): void
+    public @org.jetbrains.annotations.Nullable method get(): java.lang.Object
+}
+
+@kotlin.Metadata
+public final class D {
+    // source: 'delegateMethodIsNonOverridable.kt'
+    private final @org.jetbrains.annotations.NotNull field x$delegate: kotlin.reflect.KProperty0
+    inner (anonymous) class D$x$2$1
+    public method <init>(): void
+    public method getX(): int
+    private static method getY$delegate(p0: D): java.lang.Object
+    public method getY(): int
+}
+
+@kotlin.Metadata
+public final class DelegateMethodIsNonOverridableKt {
+    // source: 'delegateMethodIsNonOverridable.kt'
+    private final static field a: int
+    private final static field b: int
+    static method <clinit>(): void
+    public final static method getA(): int
+    public final static method getB(): int
+}