Create RedundantLabelMigrationInspection

#KT-36262

idea/testData/inspectionsLocal/redundantLabelMigration/.inspection

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+org.jetbrains.kotlin.idea.inspections.migration.RedundantLabelMigrationInspection

idea/testData/inspectionsLocal/redundantLabelMigration/simple.kt

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+// LANGUAGE_VERSION: 1.4
+// PROBLEM: none
+// ERROR: Target label does not denote a function
+
+fun testValLabelInReturn() {
+    L@ val fn = { <caret>return@L }
+    fn()
+}

idea/testData/inspectionsLocal/redundantLabelMigration/simple2.kt

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+// LANGUAGE_VERSION: 1.4
+// DISABLE-ERRORS
+
+fun testValLabelInReturn() {
+    <caret>L@ val fn = { return@L }
+    fn()
+}

idea/testData/inspectionsLocal/redundantLabelMigration/simple2.kt.after

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+// LANGUAGE_VERSION: 1.4
+// DISABLE-ERRORS
+
+fun testValLabelInReturn() {
+    val fn = { return@L }
+    fn()
+}