chore: update CI test est_time values (#22565)

Co-authored-by: Cheng Wan <chwan@rice.edu>
Co-authored-by: sglang-bot <sglang-bot@users.noreply.github.com>
Co-authored-by: Cheng Wan <54331508+ch-wan@users.noreply.github.com>

test/registered/utils/test_log_utils.py

@@ -9,7 +9,7 @@ from pathlib import Path
 from sglang.srt.utils.log_utils import create_log_targets, log_json
 from sglang.test.ci.ci_register import register_cpu_ci
 
-register_cpu_ci(est_time=4, suite="stage-a-test-cpu")
+register_cpu_ci(est_time=3, suite="stage-a-test-cpu")
 
 
 class TestLogUtils(unittest.TestCase):