[Test] Migrate AbstractExtendedFirDiagnosticsTest to new infrastructure

compiler/fir/analysis-tests/testData/resolve/extendedCheckers/unused/localVariable.kt

@@ -0,0 +1,42 @@
+import kotlin.reflect.KProperty
+
+class Outer {
+    fun foo() {
+        class Local {
+            fun bar() {
+                <!UNUSED_VARIABLE{LT}!>val <!UNUSED_VARIABLE{PSI}!>x<!> = y<!>
+            }
+        }
+    }
+
+    val y = ""
+}
+
+fun f() {
+    val a = 1
+
+    fun g(): Int {
+        return a
+    }
+}
+
+
+fun foo(v: Int) {
+    <!UNUSED_VARIABLE{LT}!>val <!UNUSED_VARIABLE{PSI}!>d<!>: Int by Delegate<!>
+    <!UNUSED_VARIABLE{LT}!>val <!UNUSED_VARIABLE{PSI}!>a<!>: Int<!>
+    <!UNUSED_VARIABLE{LT}!>val <!UNUSED_VARIABLE{PSI}!>b<!> = 1<!>
+    val c = 2
+
+    <!UNUSED_VARIABLE{LT}!>@Anno
+    val <!UNUSED_VARIABLE{PSI}!>e<!>: Int<!>
+
+    foo(c)
+}
+
+object Delegate {
+    operator fun getValue(instance: Any?, property: KProperty<*>) = 1
+    operator fun setValue(instance: Any?, property: KProperty<*>, value: String) {}
+}
+
+@Target(AnnotationTarget.LOCAL_VARIABLE)
+annotation class Anno