all: cleanup the APIs for initializing genesis (#25473)

* all: polish tests

* core: apply feedback from Guillaume

* core: fix comment

tests/state_test.go

@@ -193,7 +193,7 @@ func runBenchmark(b *testing.B, t *StateTest) {
 				return
 			}
 			vmconfig.ExtraEips = eips
-			block := t.genesis(config).ToBlock(nil)
+			block := t.genesis(config).ToBlock()
 			_, statedb := MakePreState(rawdb.NewMemoryDatabase(), t.json.Pre, false)
 
 			var baseFee *big.Int

tests/state_test_util.go

@@ -184,7 +184,7 @@ func (t *StateTest) RunNoVerify(subtest StateSubtest, vmconfig vm.Config, snapsh
 		return nil, nil, common.Hash{}, UnsupportedForkError{subtest.Fork}
 	}
 	vmconfig.ExtraEips = eips
-	block := t.genesis(config).ToBlock(nil)
+	block := t.genesis(config).ToBlock()
 	snaps, statedb := MakePreState(rawdb.NewMemoryDatabase(), t.json.Pre, snapshotter)
 
 	var baseFee *big.Int