"Remove redundant let" inspection: do not report for long call chains #KT-26289 Fixed

idea/testData/inspectionsLocal/replaceSingleLineLet/simple.kt

@@ -0,0 +1,7 @@
+// WITH_RUNTIME
+
+fun test(s: String?): Int? {
+    return s?.let<caret> {
+        it.length
+    }
+}