[clang] Revert "[clang] Reland: Instantiate concepts with sugared template arguments (#101782)" (PR #102551)

[Matheus Izvekov via cfe-commits]

mizvekov wrote:

> The description specifies "Reverted due to both regression reported on PR and https://github.com/llvm/llvm-project/issues/102353" but somehow the commit message does not include the reason.
> 
> (I just tried to look at reverts without reasons and remind the authors.)

I don't understand how that happened either. I merged through the iPhone GitHub App, for what it's worth, and I didn't edit the commit message before confirming.

https://github.com/llvm/llvm-project/pull/102551