Replace assertions with ValueErros on distilbert model
Co-author: @batese2001
This is an extended PR from [here](https://github.com/huggingface/transformers/pull/20432)  for new valid-checks to improve _code quality._

This raises exceptions on Multi-head Attention models for following specified conditions on the _Distilbert_ model.

This successfully replaces assertions with ValueErrors with the _Distilbert_ model related to #12789.

Would you be open to me changing assertions if I encounter other ones?

To: @younesbelkada
_The documentation is not available anymore as the PR was closed or merged._<|||||>This is a new PR of my own based on your suggestion from [here](https://github.com/huggingface/transformers/pull/20375). files which improved to pass all the validity checks. 
Can I ask for your further suggestions for this PR to be merged? 
Any comments will be very appreciated! 

Below mentions of PR #12789 is a related PR regarding the replacement of assertions with raising exceptions with conditions that are contrary to the pre-defined conditions.
<|||||>Hi @JuheonChu ! 👋
Thanks for the PR ;) will review it asap and let you know!<|||||>Thank you @younesbelkada  for providing us with valuable suggestions! We will make changes and make anotehr PR! 
Sincerely appreciate it :)<|||||>No worries @JuheonChu ! 
As I made you some suggestions, actually you can directly continue on this PR, let me guide you through this step by step: 
Step 1: Go to "file changed" (top right of the github UI of this PR):
<img width="921" alt="Screenshot 2022-11-25 at 22 17 47" src="https://user-images.githubusercontent.com/49240599/204059724-181f2dbc-9e09-4031-bb8c-3499b3ab12ce.png">

Step 2: For each suggestion, click on "Add suggestion to batch", to add each suggestion
<img width="921" alt="Screenshot 2022-11-25 at 22 18 59" src="https://user-images.githubusercontent.com/49240599/204059801-2e1f1a1a-cf9b-43a9-8e9b-bf8d43ea4b84.png">

Step 3: Once you have added all the suggestions (make sure to add all of them), a pop up bar will appear on the top-right corner, and you can just click to it, and the suggestions will be pushed ;) 

<img width="1467" alt="Screenshot 2022-11-25 at 22 19 43" src="https://user-images.githubusercontent.com/49240599/204059837-7f8bf1fc-4c63-4234-8dae-48b52b38eb20.png">

This way no need to open a new PR each time we do a suggestion ;) ! Let me know if anything is unclear! <|||||>Due to the reformatting of jupyter files, I created a new PR [here](https://github.com/huggingface/transformers/pull/20463) which passes all the validation checks. I apologize for any inconvenience, but do you mind if you can check  [here](https://github.com/huggingface/transformers/pull/20463)?

To: @younesbelkada <|||||>Sure! I propose to close this PR as we moved everything on the other PR ;)