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

We exclude testData pattern from copyright scope

analysis/low-level-api-fir/testData/getOrBuildFir/inImport/firstImportNamePartScript.txt

@@ -0,0 +1,12 @@
+KT element: KtNameReferenceExpression
+FIR element: FirImportImpl
+FIR source kind: KtRealSourceElementKind
+
+FIR element rendered:
+import a.b.c
+
+FIR FILE:
+FILE: [ResolvedTo(IMPORTS)] firstImportNamePartScript.kts
+    context(<script>@kotlin.script.templates.standard.ScriptTemplateWithArgs)
+    SCRIPT: [ResolvedTo(RAW_FIR)] 
+        [ResolvedTo(RAW_FIR)] lval args: R|kotlin/Array<kotlin/String>|