[tests] Disable concurrent Sparkplug for some tests

... setting too low --max-old-space-size value.

Fixes: v8:12725
Change-Id: I5b1b533992d6b1024e81263525ed90914582e27a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3695594
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Auto-Submit: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81107}

test/mjsunit/ignition/regress-672027.js

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --max-old-space-size=100
+// Flags: --max-old-space-size=100 --no-concurrent-sparkplug
 
 (function() {
   var source = "[]"

test/mjsunit/regress/regress-3976.js

@@ -25,7 +25,7 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Flags: --max-old-space-size=60 --check-handle-count
+// Flags: --max-old-space-size=60 --check-handle-count --no-concurrent-sparkplug
 
 table = [];