kotlin tests: sync dataflow/foreach test inputs and K2 expected output

Copy K1's richer C2.kt (which includes test2, test3 and l.get(0) in test)
into test-kotlin2. K2 in -language 2.0 mode already tracks dataflow through
array.set() and indirect wrapper calls, so the additional tests produce results
identical to K1.

The expected files for test-kotlin1 and test-kotlin2 are now byte-identical for
this test.

Verified:
- test-kotlin1 (kotlinc 2.3.20 / -language 1.9): all tests pass
- test-kotlin2 (kotlinc 2.4.0 / -language 2.0): all tests pass

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

java/ql/test-kotlin2/library-tests/dataflow/foreach/C2.kt

@@ -8,6 +8,7 @@ class C2 {
         val l = arrayOf(taint("a"), "")
         sink(l)
         sink(l[0])
+        sink(l.get(0))
         for (i in l.indices) {
             sink(l[i])
         }
@@ -15,4 +16,25 @@ class C2 {
             sink(s)
         }
     }
+
+    fun test2() {
+        val l1 = arrayOf("")
+        val l2 = arrayOf("")
+        l1[0] = taint("a")
+        l2.set(0, taint("a"))
+        sink(l1[0])
+        sink(l2[0])
+        sink(l1.get(0))
+        sink(l2.get(0))
+    }
+
+    fun setWrapper(l: Array<String>, v: String) {
+        l.set(0, v)
+    }
+    fun test3() {
+        val l = arrayOf("")
+        setWrapper(l, taint("a"))
+        sink(l[0])
+        sink(l.get(0))
+    }
 }

java/ql/test-kotlin2/library-tests/dataflow/foreach/test.expected

@@ -4,5 +4,12 @@
 | C1.java:10:44:10:46 | "a" | C1.java:19:20:19:20 | s |
 | C2.kt:8:31:8:33 | "a" | C2.kt:9:14:9:14 | l |
 | C2.kt:8:31:8:33 | "a" | C2.kt:10:14:10:17 | ...[...] |
-| C2.kt:8:31:8:33 | "a" | C2.kt:12:18:12:21 | ...[...] |
-| C2.kt:8:31:8:33 | "a" | C2.kt:15:18:15:18 | s |
+| C2.kt:8:31:8:33 | "a" | C2.kt:11:14:11:21 | get(...) |
+| C2.kt:8:31:8:33 | "a" | C2.kt:13:18:13:21 | ...[...] |
+| C2.kt:8:31:8:33 | "a" | C2.kt:16:18:16:18 | s |
+| C2.kt:23:23:23:25 | "a" | C2.kt:25:14:25:18 | ...[...] |
+| C2.kt:23:23:23:25 | "a" | C2.kt:27:14:27:22 | get(...) |
+| C2.kt:24:25:24:27 | "a" | C2.kt:26:14:26:18 | ...[...] |
+| C2.kt:24:25:24:27 | "a" | C2.kt:28:14:28:22 | get(...) |
+| C2.kt:36:29:36:31 | "a" | C2.kt:37:14:37:17 | ...[...] |
+| C2.kt:36:29:36:31 | "a" | C2.kt:38:14:38:21 | get(...) |