Revert "Increase update_hint_regression problem size to 1000 (pytorch…

…#136434)"

This reverts commit 3116fbd.

Reverted pytorch#136434 on behalf of https://github.com/ezyang due to whoops, this is too slow ([comment](pytorch#136434 (comment)))

benchmarks/dynamo/pr_time_benchmarks/benchmarks/update_hint_benchmark.py

@@ -6,10 +6,10 @@
 
 
 class Benchmark(BenchmarkBase):
-    N = 1000
+    N = 20
 
     def name(self):
-        return "update_hint_regression_1000"
+        return "update_hint_regression"
 
     def description(self):
         return "information at https://github.com/pytorch/pytorch/pull/129893"