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

compiler/testData/diagnostics/tests/callableReference/bound/controlFlow.fir.kt

@@ -1,3 +1,5 @@
+// !DIAGNOSICS: +UNUSED_EXPRESSION
+
 fun unusedExpression(s: String) {
     s::hashCode
     s::class

compiler/testData/diagnostics/tests/callableReference/bound/controlFlow.kt

@@ -1,3 +1,5 @@
+// !DIAGNOSICS: +UNUSED_EXPRESSION
+
 fun unusedExpression(s: String) {
     <!UNUSED_EXPRESSION!>s::hashCode<!>
     <!UNUSED_EXPRESSION!>s::class<!>

compiler/testData/diagnostics/tests/callableReference/unused.fir.kt

@@ -1,3 +1,4 @@
+// !DIAGNOSICS: +UNUSED_EXPRESSION
 fun foo() {
 
 }
@@ -20,4 +21,4 @@ fun test() {
     A::B
     A::foo
     A::bar
-}
+}

compiler/testData/diagnostics/tests/callableReference/unused.kt

@@ -1,3 +1,4 @@
+// !DIAGNOSICS: +UNUSED_EXPRESSION
 fun foo() {
 
 }
@@ -20,4 +21,4 @@ fun test() {
     <!UNUSED_EXPRESSION!>A::B<!>
     <!UNUSED_EXPRESSION!>A::foo<!>
     <!UNUSED_EXPRESSION!>A::bar<!>
-}
+}