Should raise an exception if `break` called in ensure; fix #3721

mrbgems/mruby-compiler/core/codegen.c

@@ -2948,7 +2948,7 @@ loop_break(codegen_scope *s, node *tree)
       genop_peep(s, MKOP_A(OP_POPERR, 1), NOVAL);
       loop = loop->prev;
     }
-    while (loop && loop->type == LOOP_RESCUE) {
+    while (loop && (loop->type == LOOP_RESCUE || loop->type == LOOP_BEGIN)) {
       loop = loop->prev;
     }
     if (!loop) {