[material-ui][TextField] Fix the Textarea link in the multiline section

[k-utsumi]

• I have followed (at least) the PR section of the contributing guide.

[ZeeshanTamboli]

@samuelsycamore What do you think of this? Can you take a look?

[k-utsumi]

ref: https://mui.com/material-ui/react-text-field/#multiline

Change link

• before
  https://mui.com/material-ui/react-textarea-autosize/
• after
  https://mui.com/base-ui/react-textarea-autosize/

[samuelsycamore]

I can see reasonable arguments on both sides, and I don't have a strong opinion either way. That said, I would err on the side of leaving this as is for now. It's a little annoying to be redirected to a different page like this, but the alternative is that the user would leave the Material UI docs and land in the Base UI docs without any understanding of why. I think it's important for anyone using the Textarea Autosize component in Material UI to know that it will be removed. Alternatively, we could change the link and add a note to the Base UI page explaining why Material UI users are landing there. I'm curious what @danilo-leal thinks about this.

[danilo-leal]

Seems like a safe change; I think it's okay to do it. Though I'd do a bit more to get to @samuelsycamore's recommendation to give more context:

• Add a "deprecated" chip to the Textarea sidebar page item on the Material UI docs to speed up the warning that visitors would find upon actually visiting the page
• Mention that we're using Base UI's Textarea component on the Multiline paragraph of the Text Field page in Material UI. Maybe here we could give the extra context @samuelsycamore is suggesting: add a callout to not only say that we're using Base UI's component, but also why.

(And on a more tactical note, I'd point this PR to next!)