[infra] Add alexschulze@ as infra owner

Change-Id: Ia2cf7a509736ef6a9400b81a5726c717ac3c82b2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3763869Reviewed-by: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Hannes Payer <hpayer@chromium.org>
Auto-Submit: Alexander Schulze <alexschulze@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81768}

INFRA_OWNERS

-machenbach@chromium.org
-tmrts@chromium.org
+alexschulze@chromium.org
 almuthanna@chromium.org
 liviurau@chromium.org
+machenbach@chromium.org
+tmrts@chromium.org