Change state cache size default to 32 (#7101)

Cherry-picking #7055 from `holesky-rescue` branch to the clean `release-v7.0.0` branch.

Author: jimmygchen

beacon_node/src/cli.rs

@@ -812,7 +812,7 @@ pub fn cli_app() -> Command {
                 .long("state-cache-size")
                 .value_name("STATE_CACHE_SIZE")
                 .help("Specifies the size of the state cache")
-                .default_value("128")
+                .default_value("32")
                 .action(ArgAction::Set)
                 .display_order(0)
         )

book/src/help_bn.md

@@ -386,7 +386,7 @@ Options:
       --slots-per-restore-point <SLOT_COUNT>
           DEPRECATED. This flag has no effect.
       --state-cache-size <STATE_CACHE_SIZE>
-          Specifies the size of the state cache [default: 128]
+          Specifies the size of the state cache [default: 32]
       --suggested-fee-recipient <SUGGESTED-FEE-RECIPIENT>
           Emergency fallback fee recipient for use in case the validator client
           does not have one configured. You should set this flag on the

lighthouse/tests/beacon_node.rs

@@ -1873,7 +1873,7 @@ fn block_cache_size_flag() {
 fn state_cache_size_default() {
     CommandLineTest::new()
         .run_with_zero_port()
-        .with_config(|config| assert_eq!(config.store.state_cache_size, new_non_zero_usize(128)));
+        .with_config(|config| assert_eq!(config.store.state_cache_size, new_non_zero_usize(32)));
 }
 #[test]
 fn state_cache_size_flag() {