[LL] testdata for KTIJ-21468

ensure that for each destructuring declaration entry exists FirProperty

analysis/low-level-api-fir/testdata/getOrBuildFir/declarations/destructuringEntry.kt

@@ -0,0 +1,9 @@
+/*
+ * Copyright 2010-2022 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+// WITH_STDLIB
+fun main() {
+    val (<expr>a</expr>, b) = 1 to 2
+}

analysis/low-level-api-fir/testdata/getOrBuildFir/declarations/destructuringEntry.txt

@@ -0,0 +1,6 @@
+KT element: KtDestructuringDeclarationEntry
+FIR element: FirPropertyImpl
+FIR source kind: KtRealSourceElementKind
+
+FIR element rendered:
+lval a: R|kotlin/Int| = R|<local>/<destruct>|.R|SubstitutionOverride<kotlin/Pair.component1: R|kotlin/Int|>|()