FieldTracker infinite recursion on deleting object

## Problem

Call `obj.delete()` results in:

```
Fatal Python error: _Py_CheckRecursiveCall: Cannot recover from stack overflow.
Python runtime state: initialized

Current thread 0x00007f955a596280 (most recent call first):
File "/home/brian/.asdf/installs/python/3.9.7/lib/python3.9/abc.py", line 119 in __instancecheck__
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/django/db/models/sql/query.py", line 1443 in build_filter
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/django/db/models/sql/query.py", line 1562 in _add_q
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/django/db/models/sql/query.py", line 1532 in add_q
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/django/db/models/query.py", line 1445 in _filter_or_exclude_inplace
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/django/db/models/query.py", line 1438 in _filter_or_exclude
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/django/db/models/query.py", line 1420 in filter
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/django/db/models/manager.py", line 85 in manager_method
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/django/db/models/base.py", line 724 in refresh_from_db
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 375 in inner
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/django/db/models/query_utils.py", line 178 in __get__
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 75 in __get__
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 208 in get_field_value
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 234 in
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 234 in current
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 216 in set_saved_fields
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 184 in __exit__
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 375 in inner
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/django/db/models/query_utils.py", line 178 in __get__
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 75 in __get__
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 208 in get_field_value
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 234 in
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 234 in current
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 216 in set_saved_fields
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 184 in __exit__
File "/home/brian/.cache/pypoetry/virtualenvs/karaage-uhi1oUwy-py3.9/lib/python3.9/site-packages/model_utils/tracker.py", line 375 in inner
[...]
```

## Environment

- Django Model Utils version: 4.2.0
- Django version: 4.1.1
- Python version: 3.9.7

Reproduce obj.delete() with Django Model Utils 4.2.0, Django 4.1.1, and Python 3.9.7, then trace the FieldTracker call chain shown in model_utils/tracker.py alongside Django's refresh_from_db and query code. Done means deletion no longer causes the reported recursive stack overflow, with regression coverage for the failing scenario.

Written by the indexing model from the issue text.