Increase sepolia gas limit to 60m (#15253)

Author: terencechain

changelog/tt_rice.md

@@ -0,0 +1,3 @@
+### Changed
+
+- Increase sepolia gas limit to 60M.

config/params/testnet_sepolia_config.go

@@ -50,6 +50,7 @@ func SepoliaConfig() *BeaconChainConfig {
 	cfg.FuluForkVersion = []byte{0x90, 0x00, 0x00, 0x75} // TODO: Define sepolia fork version for fulu. This is a placeholder value.
 	cfg.TerminalTotalDifficulty = "17000000000000000"
 	cfg.DepositContractAddress = "0x7f02C3E3c98b133055B8B348B2Ac625669Ed295D"
+	cfg.DefaultBuilderGasLimit = uint64(60000000)
 	cfg.InitializeForkSchedule()
 	return cfg
 }