JS: move more test to box tests

js/js.translator/testData/box/jsCode/break.kt

@@ -0,0 +1,19 @@
+package foo
+
+fun box(): String {
+    var c: Int = 0
+
+    js("""
+        for (var i = 0; i < 10; i++) {
+            c = i;
+
+            if (i === 3) {
+                break;
+            }
+        }
+    """)
+
+    assertEquals(3, c)
+
+    return "OK"
+}