The Bug:

Sniffers aren't required for the "Two by Two" advancement.

Steps to Reproduce:

1. Award yourself with the "The Parrots and the Bats" advancement by using command provided below.

   /advancement grant @s only minecraft:husbandry/breed_an_animal

2. Open your advancements menu and locate the "Two by Two" advancement and take note of its current progression.
3. Summon two sniffers and breed them.
4. Open your advancements menu once again and look at the progression of the "Two by Two" advancement.
5. Take note as to whether or not camels are required for the "Two by Two" advancement.

Observed Behavior:

Sniffers aren't required for the "Two by Two" advancement.

Expected Behavior:

Sniffers would be required for the "Two by Two" advancement.