tests: Reduce the # of iterations in safekeeper::test_random_schedules (

#9182)

To make it faster. On my laptop, it takes about 30 before this commit.
In the arm64 debug variant in CI, it takes about 120 s. Reduce it by
factor of 4.

safekeeper/tests/random_test.rs

@@ -9,15 +9,15 @@ use crate::walproposer_sim::{
 
 pub mod walproposer_sim;
 
-// Generates 2000 random seeds and runs a schedule for each of them.
+// Generates 500 random seeds and runs a schedule for each of them.
 // If you see this test fail, please report the last seed to the
 // @safekeeper team.
 #[test]
 fn test_random_schedules() -> anyhow::Result<()> {
     let clock = init_logger();
     let mut config = TestConfig::new(Some(clock));
 
-    for _ in 0..2000 {
+    for _ in 0..500 {
         let seed: u64 = rand::thread_rng().gen();
         config.network = generate_network_opts(seed);