Fix GH-12558 Escape \N and \n in generated stubs

[kocsismate]

No description provided.

[nielsdos]

Thanks for looking into this so quickly!
Minor nit for the escaping of \n: the small n does not need to be escaped
Also: doesn't this need to target 8.1 as it's a bugfix for the stub generator and may be used for PECL extensions?

[kocsismate]

Also: doesn't this need to target 8.1 as it's a bugfix for the stub generator and may be used for PECL extensions?

I was considering this option, but I ended up targeting only 8.3 (edit: I mistakenly used to target master) as the bug didn't seem widespread. However, since the original fix for \n was introduced in PHP 8.2, I'll also add my fix to this version as well.

We have to escape \N because of this C++23 proposal: https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/p2071r2.html

Aha! Thanks for the explanation :)

[nielsdos]

Thanks!