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

compiler/testData/diagnostics/tests/variance/privateToThis/FunctionCall.kt

@@ -3,7 +3,7 @@ fun <T> getT(): T = null!!
 class Test<in I> {
     private fun foo() : I = getT()
 
-    fun apply(<!UNUSED_PARAMETER!>i<!>: I) {}
+    fun apply(i: I) {}
 
     init {
         foo()

compiler/testData/diagnostics/tests/variance/privateToThis/GetVal.kt

@@ -8,7 +8,7 @@ class Test<in I, out O> {
         apply(this.i)
     }
 
-    fun apply(<!UNUSED_PARAMETER!>i<!>: I) {}
+    fun apply(i: I) {}
 
     fun test() {
         apply(i)