[Live Content Affected] Spawn eggs can no longer be placed on deny blocks

Summary:
In previous versions, players could place spawn eggs for custom entities in locations that had deny blocks located under. This is no longer possible.

Verification Build:
1.16.221

Regression Builds:
I am not entirely sure when this change happened. But I know it worked in 1.16.20 and I am fairly certain it worked in 1.16.201

Impact:
In our map `Mutant Mob Pit`, the main area is protected with deny blocks. The player previously was able to gain spawn egg items and place them in that area, but during a recent update, that is no longer available. This can confuse the player to not know why they cannot place the item in an area that seems like it should be able to placed. I have tested `can_place_on` tags as well, which do not work either. But considering these items are given from a trade, I cannot include `can_place_on` in the trade table regardless.

Repro Steps:
1. Download 'Mutant Mob Pit'
2. `/function npc/skip_tutorial`
3. `/give @p ldz:healing_spell_spawn_egg`

Observed Results:
Player cannot place the egg because of the deny blocks located at Y=0 under the map.

Expected Results:
Previously the player could place the spawn egg, with the deny blocks present.

Notes:
This previously did work. To alter the map on our end, would be difficult for us, especially since we do not have the ability to add `can_place_on` to trade tables. Once the area is left (about 50 blocks), the eggs can be placed. I am not entirely sure when this change happened. But I know it worked in 1.16.20 and I am fairly certain it worked in 1.16.201