BUG: Patch maybe_convert_objects uint64 handling
Makes method robust against known `numpy` bug that you can't compare `uint64` against `int64`
because they are casted to `float64` during the comparison, causing truncation.

xref #14937.
Follow-up to #14916.
## [Current coverage](https://codecov.io/gh/pandas-dev/pandas/pull/14951?src=pr) is 84.64% (diff: 100%)
> Merging [#14951](https://codecov.io/gh/pandas-dev/pandas/pull/14951?src=pr) into [master](https://codecov.io/gh/pandas-dev/pandas/branch/master?src=pr) will not change coverage

```diff
@@             master     #14951   diff @@
==========================================
  Files           144        144          
  Lines         51021      51021          
  Methods           0          0          
  Messages          0          0          
  Branches          0          0          
==========================================
  Hits          43188      43188          
  Misses         7833       7833          
  Partials          0          0          
```

> Powered by [Codecov](https://codecov.io?src=pr). Last update [f79bc7a...987ae5c](https://codecov.io/gh/pandas-dev/pandas/compare/f79bc7a9d128187f3a93a3dae84ff03f4f4a62f4...987ae5c484d04e55704a9bbdebbfd96787b0a4f8?src=pr) thanks!