Add memory capacity tags/serialization

Adds typ tags to GPU tests for when a test machine has more or less than
16 GB of system memory. Similar logic is then used to serialize two
cases where tests are flaky due to allocating 16 GB of memory on systems
with 8 GB of memory.

Bug: 373852610, 412955603
Change-Id: I9c834f9ed8092aaf29ad7e942f5e328ec6206c16
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6499149
Commit-Queue: Brian Sheedy <bsheedy@chromium.org>
Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1454728}