[test] Shard some slower bytecode graph builder tests.

This CL splits up some long-running bytecode graph builder tests.
There's a lot of working going on here that probably should be split
up into smaller tests and/or mjsunit tests once we have the full
ignition pipeline. This one just targets the top offenders for now.

R=rmcilroy@chromium.org, oth@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1699113002

Cr-Commit-Position: refs/heads/master@{#34039}