This reverts commit f01a6098.

Reason for revert: Consistent TSan failures: https://crbug.com/v8/12713

Original change's description:
> [baseline] Enable concurrent sparkplug
>
> Bug: v8:12054
> Change-Id: I1b0ee1a9541a75412b882b259e421aa6e88317da
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3259658
> Auto-Submit: Victor Gomes <victorgomes@chromium.org>
> Reviewed-by: Toon Verwaest <verwaest@chromium.org>
> Commit-Queue: Toon Verwaest <verwaest@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#79485}

Bug: v8:12054
Change-Id: Ide6bbac8c280a1373c5082bbe5356a205f3396c5
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3528496
Auto-Submit: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#79492}