fix: use hexutil bytes for blobs bundle (#12623)

encoding/bytesutil/BUILD.bazel

@@ -16,6 +16,7 @@ go_library(
     deps = [
         "//config/fieldparams:go_default_library",
         "//consensus-types/primitives:go_default_library",
+        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
         "@com_github_pkg_errors//:go_default_library",
     ],
 )
@@ -35,5 +36,6 @@ go_test(
         "//config/fieldparams:go_default_library",
         "//testing/assert:go_default_library",
         "//testing/require:go_default_library",
+        "@com_github_ethereum_go_ethereum//common/hexutil:go_default_library",
     ],
 )

encoding/bytesutil/bytes.go

@@ -3,6 +3,8 @@ package bytesutil
 
 import (
 	"fmt"
+
+	"github.com/ethereum/go-ethereum/common/hexutil"
 )
 
 // ToBytes48Array is a convenience method for converting an array of
@@ -104,6 +106,18 @@ func SafeCopy2d32Bytes(ary [][32]byte) [][32]byte {
 	return nil
 }
 
+// SafeCopy2dHexUtilBytes will copy and return a non-nil 2d hex util byte slice, otherwise it returns nil.
+func SafeCopy2dHexUtilBytes(ary []hexutil.Bytes) [][]byte {
+	if ary != nil {
+		copied := make([][]byte, len(ary))
+		for i, a := range ary {
+			copied[i] = SafeCopyBytes(a)
+		}
+		return copied
+	}
+	return nil
+}
+
 // ReverseBytes32Slice will reverse the provided slice's order.
 func ReverseBytes32Slice(arr [][32]byte) [][32]byte {
 	for i, j := 0, len(arr)-1; i < j; i, j = i+1, j-1 {

encoding/bytesutil/bytes_test.go

@@ -6,6 +6,7 @@ import (
 	"reflect"
 	"testing"
 
+	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/prysmaticlabs/prysm/v4/encoding/bytesutil"
 	"github.com/prysmaticlabs/prysm/v4/testing/assert"
 )
@@ -162,6 +163,14 @@ func TestSafeCopy2d32Bytes(t *testing.T) {
 	assert.DeepEqual(t, input, output)
 }
 
+func TestSafeCopy2dHexUtilBytes(t *testing.T) {
+	input := make([]hexutil.Bytes, 2)
+	input[0] = hexutil.Bytes{'a'}
+	input[1] = hexutil.Bytes{'b'}
+	output := bytesutil.SafeCopy2dHexUtilBytes(input)
+	assert.DeepEqual(t, output, [][]byte{{'a'}, {'b'}})
+}
+
 func TestToBytes48Array(t *testing.T) {
 	tests := []struct {
 		a [][]byte