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

We exclude testData pattern from copyright scope

analysis/low-level-api-fir/testData/getOrBuildFir/expressions/isExpressionScript.txt

@@ -0,0 +1,16 @@
+KT element: KtIsExpression
+FIR element: FirTypeOperatorCallImpl
+FIR source kind: KtRealSourceElementKind
+
+FIR element rendered:
+(R|<local>/x| is R|kotlin/String|)
+
+FIR FILE:
+FILE: [ResolvedTo(IMPORTS)] isExpressionScript.kts
+    context(<script>@R|kotlin/script/templates/standard/ScriptTemplateWithArgs|)
+    SCRIPT: [ResolvedTo(TYPES)] 
+        [ResolvedTo(RAW_FIR)] lval args: R|kotlin/Array<kotlin/String>|
+
+        public final [ResolvedTo(BODY_RESOLVE)] fun foo([ResolvedTo(BODY_RESOLVE)] x: R|kotlin/Any|): R|kotlin/Boolean| {
+            ^foo (R|<local>/x| is R|kotlin/String|)
+        }