StartCollideEvent is raised for fixtures that should not collide

[koteq]

Description

The StartCollideEvent is incorrectly raised for fixtures that shouldn't collide, given their layers and masks.

Reproduction

A simple example is Remilia being slowed down by a spill of glue.

// glue
var fixtureACollisionMask = 10;  // ItemMask = Impassable | HighImpassable
var fixtureACollisionLayer = 20;  // SlipLayer = MidImpassable | LowImpassable
		
// bat
var fixtureBCollisionMask = 10; // FlyingMobMask = Impassable | HighImpassabl
var fixtureBCollisionLayer = 65; // FlyingMobLayer = Opaque | BulletImpassable
		
var shouldCollide = !((fixtureACollisionMask & fixtureBCollisionLayer) == 0x0 &&
             (fixtureBCollisionMask & fixtureACollisionLayer) == 0x0);  // False

I tried to debug it a little, and it looks like CollideContacts() skips the ShouldCollide check when the ContactFlags.Filter isn't set, and it seems the flag isn't being set correctly.

https://github.com/space-wizards/RobustToolbox/blob/ace8334a3e39ffe7d3ad94c5caba48d245ddfe7b/Robust.Shared/Physics/Systems/SharedPhysicsSystem.Contacts.cs#L405-L418