beacon/params: new checkpoints (ethereum#31470)

This PR updates beacon checkpoints. The checkpoints are now stored as
embedded hex files, in the same format that
ethereum#31469 uses.

Author: zsfelfoldi

beacon/params/checkpoint_holesky.hex

@@ -0,0 +1 @@
+0xf5606a019f0f1006e9ec2070695045f4334450362a48da4c5965314510e0b4c3

beacon/params/checkpoint_mainnet.hex

@@ -0,0 +1 @@
+0x3c0cb4aa83beded1803d262664ba4392b1023f334d9cca02dc3a6925987ebe91

beacon/params/checkpoint_sepolia.hex

@@ -0,0 +1 @@
+0xa8d56457aa414523d93659aef1f7409bbfb72ad75e94d917c8c0b1baa38153ef

beacon/params/networks.go

@@ -17,14 +17,25 @@
 package params
 
 import (
+	_ "embed"
+
 	"github.com/ethereum/go-ethereum/common"
 )
 
+//go:embed checkpoint_mainnet.hex
+var checkpointMainnet string
+
+//go:embed checkpoint_sepolia.hex
+var checkpointSepolia string
+
+//go:embed checkpoint_holesky.hex
+var checkpointHolesky string
+
 var (
 	MainnetLightConfig = (&ChainConfig{
 		GenesisValidatorsRoot: common.HexToHash("0x4b363db94e286120d76eb905340fdd4e54bfe9f06bf33ff6cf5ad27f511bfe95"),
 		GenesisTime:           1606824023,
-		Checkpoint:            common.HexToHash("0x6509b691f4de4f7b083f2784938fd52f0e131675432b3fd85ea549af9aebd3d0"),
+		Checkpoint:            common.HexToHash(checkpointMainnet),
 	}).
 		AddFork("GENESIS", 0, []byte{0, 0, 0, 0}).
 		AddFork("ALTAIR", 74240, []byte{1, 0, 0, 0}).
@@ -35,7 +46,7 @@ var (
 	SepoliaLightConfig = (&ChainConfig{
 		GenesisValidatorsRoot: common.HexToHash("0xd8ea171f3c94aea21ebc42a1ed61052acf3f9209c00e4efbaaddac09ed9b8078"),
 		GenesisTime:           1655733600,
-		Checkpoint:            common.HexToHash("0x456e85f5608afab3465a0580bff8572255f6d97af0c5f939e3f7536b5edb2d3f"),
+		Checkpoint:            common.HexToHash(checkpointSepolia),
 	}).
 		AddFork("GENESIS", 0, []byte{144, 0, 0, 105}).
 		AddFork("ALTAIR", 50, []byte{144, 0, 0, 112}).
@@ -47,7 +58,7 @@ var (
 	HoleskyLightConfig = (&ChainConfig{
 		GenesisValidatorsRoot: common.HexToHash("0x9143aa7c615a7f7115e2b6aac319c03529df8242ae705fba9df39b79c59fa8b1"),
 		GenesisTime:           1695902400,
-		Checkpoint:            common.HexToHash("0x6456a1317f54d4b4f2cb5bc9d153b5af0988fe767ef0609f0236cf29030bcff7"),
+		Checkpoint:            common.HexToHash(checkpointHolesky),
 	}).
 		AddFork("GENESIS", 0, []byte{1, 1, 112, 0}).
 		AddFork("ALTAIR", 0, []byte{2, 1, 112, 0}).