Kotlin: Add FP test cases for empty blocks

Author: tamasvajk

java/ql/test/kotlin/query-tests/EmptyBlock/EmptyBlock.expected

@@ -0,0 +1,3 @@
+| Test.kt:1:1:13:1 | { ... } | This block should not be empty. Typographical error or missing code? |
+| Test.kt:2:20:4:5 | { ... } | This block should not be empty. Typographical error or missing code? |
+| Test.kt:7:9:8:9 | { ... } | This block should not be empty. Typographical error or missing code? |

java/ql/test/kotlin/query-tests/EmptyBlock/EmptyBlock.qlref

@@ -0,0 +1 @@
+Likely Bugs/Statements/EmptyBlock.ql

java/ql/test/kotlin/query-tests/EmptyBlock/Test.kt

@@ -0,0 +1,13 @@
+class Foo {
+    abstract inner class Bar {
+        abstract fun myFun(): Int
+    }
+
+    inner class Baz {
+        constructor() {
+        }
+
+        fun fn() {
+        }
+    }
+}