[Test] Disable UNUSED_* diagnostics in tests which are not belong to contolFlowAnalysis suite

compiler/testData/diagnostics/tests/when/withSubjectVariable/smartCastOnValueBoundToSubjectVariable.kt

@@ -43,7 +43,7 @@ fun test5(x: Inv<out Any?>) {
 }
 
 fun test6(x: Inv<out String?>) {
-    when (val <!UNUSED_VARIABLE!>y<!> = x.data) {
+    when (val y = x.data) {
         is String -> <!DEBUG_INFO_SMARTCAST!>x.data<!>.length // should be ok
     }
-}
+}

compiler/testData/diagnostics/tests/when/withSubjectVariable/unusedWhenSubjectVariable.fir.kt

@@ -1,8 +1,9 @@
 // !LANGUAGE: +VariableDeclarationInWhenSubject
+// !DIAGNOSTICS: +UNUSED_VARIABLE
 
 fun foo(): Any = 42
 
 fun test() {
     when (val x = foo()) {
     }
-}
+}

compiler/testData/diagnostics/tests/when/withSubjectVariable/unusedWhenSubjectVariable.kt

@@ -1,5 +1,5 @@
 // !LANGUAGE: +VariableDeclarationInWhenSubject
-// !DIAGNOSICS: +UNUSED_VARIABLE
+// !DIAGNOSTICS: +UNUSED_VARIABLE
 
 fun foo(): Any = 42