Increase the number of iterations in a test that compares rolled versus unrolled HLO for length.

A change that avoids duplicating subcomputations in XLA causes this test to fail, but we can make it work again by increasing the number of iterations.

PiperOrigin-RevId: 735875835

Author: hawkinsp

tests/lax_control_flow_test.py

@@ -2445,7 +2445,7 @@ def f(c, a):
       assert b.shape == ()
       return c, b
 
-    xs = jnp.ones((5, 3))
+    xs = jnp.ones((20, 3))
     c = jnp.ones(4)
 
     scan = lambda c, xs: lax.scan(f, c, xs)