[LL FIR] rename testdata to testData to avoid copyright generation

We exclude testData pattern from copyright scope

analysis/low-level-api-fir/testData/nonLocalDeclarationAnchors/classWithMembersScript.kts

@@ -0,0 +1,15 @@
+class A constructor(a: Int) {
+    fun boo() {
+        fun bar() {
+
+        }
+    }
+
+    val i: Int = 42
+
+    init {
+        fun foo() {
+
+        }
+    }
+}