Slurtle Mounds are targeted as if they were hostile entities

Given that the current beta is about cave content, I thought I'd bring attention to this again, even if it's pretty small.

This issue happens due to them having the "hostile" tag. It can be quite inconvenient, especially when trying to fight slurtles themselves, as the mound will most likely be prioritized.

Shouldn't they also have the "structure" tag like other similar entities (hound mounds, bee hives, etc)? This would also make it so if new non-structure targets are detected when attempting to attack, those take priority, like with other similar entities.