Error trying to use Altar of Light in 1.8

## Affected Plugin
- **Affected Plugin Name:** Vampire
- **Affected Plugin Version:** 2.13.1

## Describe your Environment
- **Server Version:** 1.8.8

## Steps to Reproduce this Bug
Try to create a potion of Holy Water

## Observed Results
https://pastebin.com/7RnQLVsq
Maybe buggy using 1.9 potion instead of 1.8

## Expected Results
A potion in the inventory