[Spec tests] Fix tests

compiler/tests-spec/testData/codegen/box/linked/expressions/built-in-types-and-their-semantics/kotlin.nothing-1/p-1/pos/1.1.kt

@@ -1,3 +1,4 @@
+// !LANGUAGE: +NewInference
 // WITH_RUNTIME
 
 /*
@@ -6,14 +7,14 @@
  * SPEC VERSION: 0.1-213
  * PLACE: expressions, built-in-types-and-their-semantics, kotlin.nothing-1 -> paragraph 1 -> sentence 1
  * NUMBER: 1
- * DESCRIPTION: todo
+ * DESCRIPTION: check kotlin.Nothing by throwing the exception
  */
 
 fun foo(): Nothing {
     throw Exception()
 }
 
-fun box() {
+fun box(): String {
     try {
         foo()
     } catch (e: Exception) {

compiler/tests-spec/testData/codegen/box/linked/expressions/built-in-types-and-their-semantics/kotlin.unit/p-1/pos/1.1.kt

@@ -5,6 +5,7 @@
  *
  * SPEC VERSION: 0.1-213
  * PLACE: expressions, built-in-types-and-their-semantics, kotlin.unit -> paragraph 1 -> sentence 1
+ * RELEVANT PLACES: expressions, equality-expressions, reference-equality-expressions -> paragraph 1 -> sentence 2
  * NUMBER: 1
  * DESCRIPTION: todo
  */
@@ -20,7 +21,7 @@ fun foo2(): Unit {
 fun foo3(): Unit {
 }
 
-fun box(){
+fun box(): String {
     val u1 = foo1()
     val u2 = foo2()
     val u3 = foo3()

compiler/tests-spec/testData/codegen/box/linked/type-system/type-kinds/built-in-types/kotlin.nothing/p-1/pos/1.2.kt

@@ -6,16 +6,16 @@
  * SPEC VERSION: 0.1-213
  * PLACE: type-system, type-kinds, built-in-types, kotlin.nothing -> paragraph 1 -> sentence 1
  * NUMBER: 2
- * DESCRIPTION: todo
+ * DESCRIPTION: check the allowance of returning Nothing where String is expected
  */
 
 
 fun foo(s: String?): String {
-    val data = s ?: throw IllegalArgumentException("not null string is expected");
+    return s ?: throw IllegalArgumentException("not null string is expected");
 }
 
-fun box() {
-    val result = "NOK"
+fun box(): String {
+    var result = "NOK"
     val b = foo("")
     try {
         val a = foo(null)

compiler/tests-spec/testData/codegen/box/linked/type-system/type-kinds/built-in-types/kotlin.nothing/testsMap.json

@@ -5,7 +5,7 @@
         {
           "specVersion": "0.1-213",
           "casesNumber": 0,
-          "description": "todo",
+          "description": "check the allowance of returning Nothing where String is expected",
           "unexpectedBehaviour": false
         },
         {