[shared-struct] Remove descriptor count check for JSSharedArrayMap

... which might fail during map configuration.

Bug: v8:12993, v8:12547
Change-Id: Ia57fe60abf4164d81a1352966f9d07016e882be9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3717993Reviewed-by: Patrick Thier <pthier@chromium.org>
Auto-Submit: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Patrick Thier <pthier@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81306}

src/diagnostics/objects-debug.cc

@@ -557,8 +557,6 @@ void Map::MapVerify(Isolate* isolate) {
       CHECK(instance_descriptors(isolate).InSharedHeap());
       if (IsJSSharedArrayMap()) {
         CHECK(has_shared_array_elements());
-        // SharedArrys have only one descriptor, the length accessor.
-        CHECK_EQ(NumberOfOwnDescriptors(), 1);
       }
     }
   }