Parrots lose their scoreboard scores when mounting players' shoulders

The Bug:

Parrots lose their scoreboard scores when mounting players' shoulders.

Steps to Reproduce:

1. Create a dummy scoreboard objective and set it to display on the sidebar by using the commands provided below.

   /scoreboard objectives add test dummy

   /scoreboard objectives setdisplay sidebar test

2. Summon a parrot and give it a score of 1 by using the command provided below.

   /scoreboard players add @e[type=minecraft:parrot,sort=nearest,limit=1] test 1

3. Tame the parrot and get it to mount your shoulder.
4. Take note as to whether or not parrots lose their scoreboard scores when mounting players' shoulders.

Observed Behavior:

Parrots lose their scoreboard scores.

Expected Behavior:

Parrots would not lose their scoreboard scores.