[KLIB][tests] Reorganize "klib dump-ir" tests

- Keep the test data under "native/native.tests/testData/klib/" dir
- Rename tests from "klib ir" to "klib dump-ir"

native/native.tests/testData/klib/dump-ir/class.sig.ir.txt

@@ -0,0 +1,8 @@
+MODULE_FRAGMENT name:<class.kt>
+  FILE fqName:test fileName:class.kt
+    CLASS CLASS name:A signature:test/A|null[0] modality:FINAL visibility:public superTypes:[<unbound IrClassPublicSymbolImpl>]
+      $this: VALUE_PARAMETER INSTANCE_RECEIVER name:<this> type:test.A
+      CONSTRUCTOR signature:test/A.<init>|<init>(){}[0] visibility:public <> () returnType:test.A [primary]
+        BLOCK_BODY
+          DELEGATING_CONSTRUCTOR_CALL 'UNBOUND IrConstructorPublicSymbolImpl'
+          INSTANCE_INITIALIZER_CALL classDescriptor='CLASS CLASS name:A signature:test/A|null[0] modality:FINAL visibility:public superTypes:[<unbound IrClassPublicSymbolImpl>]'