[FIX] core: maximum recursion because of `active` fields.

In specific situation, unlink can lead to raise a `RecursionError`:
- The model `A` has a many2one `b_id` field toward a model `B`.
This field is set with `ondelete='cascade'`.
- The model `A` has one **store** related field **no-sudo** named
`a_related` (`related='b_id.b_other_field`).
- With `ir.rule` on model `A` with a domain containing `a_related`

You have one record B `b_1` with 20 records A linked to it
(`a_1, ..., a_20`). When you try to unlink `b_1`:

Stack:

  File "...", line 543, in ...
    b_1.unlink()
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 3594, in unlink
    self.env.flush_all()

=> At this point, `a_1, ..., a_20` have already been deleted from the
database because of the 'cascade' deletion. But the ORM doesn't have
any information about this, and `a_related` (for `a_1, ..., a_20`) are
flagged to be recomputed (because it depends on `b_id.b_other_field`)

  File "/home/odoo/Documents/dev/odoo/odoo/api.py", line 732, in flush_all
    self._recompute_all()
  File "/home/odoo/Documents/dev/odoo/odoo/api.py", line 728, in _recompute_all
    self[field.model_name]._recompute_field(field)
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 6165, in _recompute_field
    field.recompute(records)
  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 1348, in recompute
    self.compute_value(record)

=> `self.compute_value(recs)` raised a `MissingError` before recalling
`compute_value` with only the first `record` (but others are still in
the prefetch)

  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 1368, in compute_value
    records._compute_field_value(self)

=> `a_related` of `record` is removed from to_compute, but only the
first record, not the rest of the records present in the prefetch set.

  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 4194, in _compute_field_value
    fields.determine(field.compute, self)
  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 100, in determine
    return needle(records, *args)
  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 689, in _compute_related
    values = [first(value[name]) for value in values]
  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 689, in <listcomp>
    values = [first(value[name]) for value in values]
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 5860, in __getitem__
    return self._fields[key].__get__(self, type(self))
  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 2772, in __get__
    return super().__get__(records, owner)
  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 1186, in __get__
    recs._fetch_field(self)
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 3162, in _fetch_field
    self._read(fnames)

=> `_read` tries to read the first record + others from the prefetch set

  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 3215, in _read
    self.with_context(active_test=False)._flush_search([], order='id')
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 4607, in _flush_search
    self.env[model_name].flush_model(field_names)
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 5560, in flush_model
    self._recompute_model(fnames)
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 6134, in _recompute_model
    self._recompute_field(field)

=> This is where the recursion starts, record compute will move forward
one by one. But sadly, the stack grows very fast, and with only a few
(already deleted) records to recompute, the issue will be generated.

  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 6165, in _recompute_field
    field.recompute(records)
  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 1348, in recompute
    self.compute_value(record)
  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 1368, in compute_value
    records._compute_field_value(self)
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 4194, in _compute_field_value
    fields.determine(field.compute, self)
  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 100, in determine
    return needle(records, *args)
  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 689, in _compute_related
    values = [first(value[name]) for value in values]
  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 689, in <listcomp>
    values = [first(value[name]) for value in values]
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 5860, in __getitem__
    return self._fields[key].__get__(self, type(self))
  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 2772, in __get__
    return super().__get__(records, owner)
  File "/home/odoo/Documents/dev/odoo/odoo/fields.py", line 1186, in __get__
    recs._fetch_field(self)
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 3162, in _fetch_field
    self._read(fnames)
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 3215, in _read
    self.with_context(active_test=False)._flush_search([], order='id')
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 4607, in _flush_search
    self.env[model_name].flush_model(field_names)
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 5560, in flush_model
    self._recompute_model(fnames)
  File "/home/odoo/Documents/dev/odoo/odoo/models.py", line 6134, in _recompute_model
    self._recompute_field(field)

How to fix it:
Move the logic of the MissingError of `_recompute_field` inside the
`recompute` directly.

Part-of: odoo/odoo#121355