Incorrect deletion of documents when using the disableOnAttributes typo setting + reduce size of the index on DB

[loiclec]

To reproduce, on Meilisearch v1.2.0 (and earlier versions):

Set the searchable attributes to [text, exact]
Set the disableOnAttributes to: [exact]

Add the following documents:

    { id: 0, text: "hello" }
    { id: 1, exact: "hello" }

Delete the document with the external id 1 (make sure to disable soft deletion).

The remaining documents are correct:

    { id: 0, text: "hello" }

But the words_fst structure in the index was incorrectly updated. It does not contain hello anymore.
As a result, if we now search for hello, we get zero results.

[curquiza]

Also reduce size of the index #3819 (comment)