ci: raise merge-tier entrypoint timeouts (H100 60->90, L4 30->45)

Both entrypoint jobs are killed mid-run by timeout_in_minutes while tests
are still passing, not by any failing test. The budgets had no headroom:
on main the H100 job timed out in 2 of the last 3 gate builds (2648, 2650)
and passed 2651 at 56/60 min; the L4 job passed at 26/30 min only with a
warm image cache. On the vLLM 0.25 wheel, model weight loading is slower
on the CI runners (like-for-like: +10 min total on H100, 1.7B TTS load
11s -> 132s on L4), which turns the coin flip into a guaranteed timeout
(build 2655).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Signed-off-by: tzhouam <tzhouam@connect.ust.hk>

.buildkite/test-merge.yml

@@ -108,7 +108,10 @@ steps:
     depends_on: upload-merge-pipeline
     steps:
       - label: "Entrypoint Test with H100"
-        timeout_in_minutes: 60
+        # The suite relaunches an OmniServer per test class (~30 model loads,
+        # incl. ten ~27.5 GiB Bagel loads); 60 min passed only ~1 in 3 runs
+        # even on main, and vLLM 0.25 weight loading needs ~10 min more.
+        timeout_in_minutes: 90
         commands:
           - pytest -s -v tests/entrypoints/ -m "advanced_model and cuda and H100" --run-level "advanced_model"
         agents:
@@ -146,7 +149,9 @@ steps:
                       type: DirectoryOrCreate
 
       - label: "Entrypoint Test with L4"
-        timeout_in_minutes: 30
+        # 30 min left no headroom for a cold image pull (~11 min for new base
+        # layers) plus per-class engine relaunches; main passed at 26/30.
+        timeout_in_minutes: 45
         commands:
           - pytest -s -v tests/entrypoints/ -m "advanced_model and cuda and L4" --run-level "advanced_model"
         agents: