Call chain --> Sequence: don't report if first call is 'groupingBy'

#KT-27104 Fixed

idea/testData/inspectionsLocal/collections/convertCallChainIntoSequence/endsWithGroupingBy.kt

@@ -0,0 +1,5 @@
+// WITH_RUNTIME
+
+fun test(list: List<Int>) {
+    list.<caret>map { it * 2 }.map { it * 3 }.map { it * 4 }.groupingBy { it }
+}

idea/testData/inspectionsLocal/collections/convertCallChainIntoSequence/endsWithGroupingBy.kt.after

@@ -0,0 +1,5 @@
+// WITH_RUNTIME
+
+fun test(list: List<Int>) {
+    list.asSequence().map { it * 2 }.map { it * 3 }.map { it * 4 }.groupingBy { it }
+}

idea/testData/inspectionsLocal/collections/convertCallChainIntoSequence/startsWithGroupingBy.kt

@@ -0,0 +1,6 @@
+// PROBLEM: none
+// WITH_RUNTIME
+
+fun test(list: List<Int>) {
+    list.<caret>groupingBy { it }.reduce { _, acc, _ -> acc }
+}