Form refresh issue after edit

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Hello, i've an issue when I edit a record :
If I delete an existing field value, save form and just after, modify another field and save form again,
my previous field to which I deleted the value, returns to its previous value.
When form is refreshed after save, If I check the React Query dev tool, the data are however good
It's occurs only when field value was previously set to null
Little precision : I use Airtable as database, and records fields that are null are not retrieved from the record data

**Steps to reproduce:**

- Select a record from post list
- if "Name" input was empty, add value, save form, and refresh stackblitz render window
- delete "Name" value
- save form
- change value of checkbox
- save form

- [https://stackblitz.com/edit/github-iq4gf4?file=src%2Fposts%2FPostEdit.tsx,src%2FdataProvider.tsx,src%2Fposts%2FPostList.tsx](https://stackblitz.com/edit/github-iq4gf4?file=src%2Fposts%2FPostEdit.tsx,src%2FdataProvider.tsx,src%2Fposts%2FPostList.tsx)

**Environment**

* React-admin version: 4.14.4
* Last version that did not exhibit the issue : 3.11.3 (yeah big jump 😅)
* React version: 17.0.0
* Browser: Chrome, Safari, Firefox

Start with the linked StackBlitz files: src/posts/PostEdit.tsx, src/dataProvider.tsx, and src/posts/PostList.tsx. Reproduce the null-value edit sequence and compare the form refresh with the React Query dev-tool data, focusing on how Airtable omits null fields. Done means a deleted value remains empty after a later field edit and save.

Written by the indexing model from the issue text.