Update the QGB minimum data commitment window error message

[rach-id]

          Thanks for sharing!

1. should the 100 be extracted to a constant?
2. I don't see why specifying a data commitment window of 99 would result in the error: "invalid average EVM block time, too short for latency limitations" because the data commitment window is not related to the average EVM block time. I would expect an error message like

const MinimumDataCommitmentWindow = 100

func validateDataCommitmentWindow(i interface{}) error {
	val, ok := i.(uint64)
	if !ok {
		return fmt.Errorf("invalid parameter type: %T", i)
	} else if val < uint64(MinimumDataCommitmentWindow) {
		return fmt.Errorf("data commitment window %v must be >= minimum data commitment window %v", val, MinimumDataCommitmentWindow)
	}
	return nil
}

Originally posted by @rootulp in #1695 (comment)