Reland "Reland "sdk: add RTC_OBJC_TYPE to ios Metal renderer classes""

This is a reland of commit 14e19b2f6ce0e284b186007124383724df0162d9

Original change's description:
> Reland "sdk: add RTC_OBJC_TYPE to ios Metal renderer classes"
>
> This is a reland of commit 89e8619bfdacfd1364bf3fc6bc5388c92629ab71
>
> Original change's description:
> > sdk: add RTC_OBJC_TYPE to ios Metal renderer classes
> >
> > Bug: webrtc:460166677
> > Change-Id: Id8883d40957e26046897632c4f6ed2d9c36bcf4e
> > Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/427320
> > Reviewed-by: Kári Helgason <kthelgason@webrtc.org>
> > Commit-Queue: Kári Helgason <kthelgason@webrtc.org>
> > Cr-Commit-Position: refs/heads/main@{#46309}
>
> Bug: webrtc:460166677
> Change-Id: Ia31eec951ca8c3dbe2389b8b0244ce0d540bfcc1
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/430900
> Commit-Queue: Kári Helgason <kthelgason@webrtc.org>
> Reviewed-by: Evan Shrubsole <eshr@webrtc.org>
> Reviewed-by: Kári Helgason <kthelgason@webrtc.org>
> Cr-Commit-Position: refs/heads/main@{#46595}

Bug: webrtc:460166677
Change-Id: I399d333f729127d8a45795b7b60b9a96511a9c17
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/442282
Reviewed-by: Evan Shrubsole <eshr@webrtc.org>
Reviewed-by: Kári Helgason <kthelgason@webrtc.org>
Commit-Queue: Philipp Hancke <philipp.hancke@googlemail.com>
Cr-Commit-Position: refs/heads/main@{#47089}