This reverts commit 2998c8d.

We need to find a better way to fix this bug. Even with this refcount
change, errors were still being seen in CI. For now we need to remove
this failing test.

…15138)

This reverts commit 2998c8d.

We need to find a better way to fix this bug. Even with this refcount
change, errors were still being seen in CI. For now we need to remove
this failing test.

We were seeing errors like:

```
* thread #8, stop reason = EXC_BAD_ACCESS (code=1, address=0x803)
  * frame #0: 0x00000001001fe944 ruby`rb_st_lookup(tab=0x00000000000007fb, key=1, value=0x00000001305b7490) at st.c:1066:22
    frame #1: 0x000000010002d658 ruby`remove_class_from_subclasses [inlined] class_get_subclasses_for_ns(tbl=0x00000000000007fb, ns_id=1) at class.c:604:9
    frame #2: 0x000000010002d650 ruby`remove_class_from_subclasses(tbl=0x00000000000007fb, ns_id=1, klass=4754039232) at class.c:620:34
    frame #3: 0x000000010002c8a8 ruby`rb_class_classext_free_subclasses(ext=0x000000011b5ce1d8, klass=4754039232, replacing=<unavailable>) at class.c:700:9
    frame #4: 0x000000010002c760 ruby`rb_class_classext_free(klass=4754039232, ext=0x000000011b5ce1d8, is_prime=true) at class.c:105:5
    frame #5: 0x00000001000e770c ruby`classext_free(ext=<unavailable>, is_prime=<unavailable>, namespace=<unavailable>, arg=<unavailable>) at gc.c:1231:5 [artificial]
    frame #6: 0x000000010002d178 ruby`rb_class_classext_foreach(klass=<unavailable>, func=(ruby`classext_free at gc.c:1228), arg=0x00000001305b75c0) at class.c:518:5
    frame #7: 0x00000001000e745c ruby`rb_gc_obj_free(objspace=0x000000012500c400, obj=4754039232) at gc.c:1282:9
    frame #8: 0x00000001000e70d4 ruby`gc_sweep_plane(objspace=0x000000012500c400, heap=<unavailable>, p=4754039232, bitset=4095, ctx=0x00000001305b76e8) at default.c:3482:21
    frame #9: 0x00000001000e6e9c ruby`gc_sweep_page(objspace=0x000000012500c400, heap=0x000000012500c540, ctx=0x00000001305b76e8) at default.c:3567:13
    frame #10: 0x00000001000e51d0 ruby`gc_sweep_step(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:3848:9
    frame #11: 0x00000001000e1880 ruby`gc_continue [inlined] gc_sweep_continue(objspace=0x000000012500c400, sweep_heap=0x000000012500c540) at default.c:3931:13
    frame #12: 0x00000001000e1754 ruby`gc_continue(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:2037:9
    frame #13: 0x00000001000e10bc ruby`newobj_cache_miss [inlined] heap_prepare(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:2056:5
    frame #14: 0x00000001000e1074 ruby`newobj_cache_miss [inlined] heap_next_free_page(objspace=0x000000012500c400, heap=0x000000012500c540) at default.c:2280:9
    frame #15: 0x00000001000e106c ruby`newobj_cache_miss(objspace=0x000000012500c400, cache=0x0000600001b00300, heap_idx=2, vm_locked=false) at default.c:2387:38
    frame #16: 0x00000001000e0d28 ruby`newobj_alloc(objspace=<unavailable>, cache=<unavailable>, heap_idx=<unavailable>, vm_locked=<unavailable>) at default.c:2411:15 [artificial]
    frame #17: 0x00000001000d7214 ruby`newobj_of [inlined] rb_gc_impl_new_obj(objspace_ptr=<unavailable>, cache_ptr=<unavailable>, klass=<unavailable>, flags=<unavailable>, wb_protected=<unavailable>, alloc_size=<unavailable>) at default.c:2490:15
    frame #18: 0x00000001000d719c ruby`newobj_of(cr=<unavailable>, klass=4313971728, flags=258, wb_protected=<unavailable>, size=<unavailable>) at gc.c:995:17
    frame #19: 0x00000001000d73ec ruby`rb_wb_protected_newobj_of(ec=<unavailable>, klass=<unavailable>, flags=<unavailable>, size=<unavailable>) at gc.c:1044:12 [artificial]
    frame #20: 0x0000000100032d34 ruby`class_alloc0(type=<unavailable>, klass=4313971728, namespaceable=<unavailable>) at class.c:803:5
```

…" (ruby#15138)

This reverts commit 2998c8d.

We need to find a better way to fix this bug. Even with this refcount
change, errors were still being seen in CI. For now we need to remove
this failing test.