Makes the Voided Brain Trauma from the Voidwalker less punishing (#5090)

## About The Pull Request
Makes the Voided Brain Trauma which you acquire when being kidnapped by
the Voidwalker no longer knock you down when you spawn nebula vomit
through vomiting. In fact, you no longer vomit at all and instead just
spawn the decal at your location. It has also been reflavored to be a
puddle which forms from liquid dripping off your body instead of vomit.
In addition to that, having the brain trauma now gives a positive
moodlet.

## Why It's Good For The Game
The brain trauma has great rp potential which is ruined by the constant
vomiting, which in turn discourages roleplay and makes people run to get
it cured as soon as possible. For a supposedly non-lethal antag, this
was arguably a fate worse than death.
With this not only can you continue playing the game as usual, but it
gives you an opportunity to actually roleplay around the brain trauma.
The #suggestions channel seems to agree that this would be a positive
change.

## Proof Of Testing
It runs and seems to function as intended
<details>
<summary>Screenshots/Videos</summary>

</details>

## Changelog
🆑
qol: made the voided brain trauma not a pain to have by removing the
knockdown it gave you
/🆑

---------

Co-authored-by: tgstation-ci[bot] <179393467+tgstation-ci[bot]@users.noreply.github.com>

code/modules/antagonists/voidwalker/voidwalker_traumas.dm

@@ -81,8 +81,11 @@
 /datum/brain_trauma/voided/on_life(seconds_per_tick, times_fired)
 	. = ..()
 
+	//BUBBER EDIT START - makes nebula vomit not painful to deal with
 	if(prob(vomit_frequency))
-		owner.vomit(MOB_VOMIT_KNOCKDOWN, vomit_type = /obj/effect/decal/cleanable/vomit/nebula, distance = 0)
+		new /obj/effect/decal/cleanable/vomit/nebula(owner.loc)
+		owner.visible_message(span_notice("a beautifully sparkling liquid drips off of [owner] and forms a puddle"), span_notice("The beautifully sparkling liquid dripping off of you forms a puddle"))
+	//BUBBER EDIT END
 
 /// Apply the space texture
 /datum/brain_trauma/voided/proc/texture_limb(atom/source, obj/item/bodypart/limb)