feat: buff all water purification methods by 8x (250ml -> 2L)

[scarf005]

Summary

SUMMARY: Balance "Buff all water purification methods by 8x (250ml -> 2L)"

Purpose of change

rationale:

1. water purification tablets are too inefficient
2. google says a single tablet can purify up to 1~2L of water

Each tablet treats up to 2 quarts of clean water or 0.8 quart of dirty water
ew, US measurements but that's not the point

Describe the solution

modified charges used in iuse::water_purifier by 1/8

Testing

2023-05-16.11-26-57.mp4

using single tablet

1. spawn a 3L bottle, a bottle (0.5L), and 2 water purification tablet
2. fill the bottles with water
3. use tablets to each bottles
4. check that both are purified

2023-05-16.11-47-46.mp4

using multiple tablets

1. spawn a 10L jerrycan, and 5 water purification tablet
2. fill the jerrycan with water
3. use tablet
4. check that the jerrycan is purified, and all tablets are used

[chaosvolt]

Airing on the side of 1 liter instead of 2 liter would also work, but whichever you prefer I guess.