Add profiling around seed trial generation to help debug slow runs.

PiperOrigin-RevId: 567208089

Author: sagipe

vizier/_src/algorithms/designers/gp_bandit.py

@@ -294,10 +294,11 @@ def _generate_seed_trials(self, count: int) -> Sequence[vz.TrialSuggestion]:
               parameters, metadata=vz.Metadata({'seeded': 'center'})
           )
       )
-    if (remaining_counts := count - len(seed_suggestions)) > 0:
-      seed_suggestions.extend(
-          self._quasi_random_sampler.suggest(remaining_counts)
-      )
+    with profiler.timeit('quasi_random_sampler_seed_trials'):
+      if (remaining_counts := count - len(seed_suggestions)) > 0:
+        seed_suggestions.extend(
+            self._quasi_random_sampler.suggest(remaining_counts)
+        )
     return seed_suggestions
 
   @_experimental_override_allowed