Alex skin's left leg is wrongly rendered on the base layer.

Verification builds: 1.14.1 / 1.14.20.2_rc2 / 1.14.25.1_rc0

Summary: Alex skin's left leg is wrongly rendered on the base layer.
Impact: All Alex skins have this issue.
Repro Steps:
1. Create a skin with a left leg blue and a right leg red.
2. Apply skin to Alex model in-game.

Observed Results: Both legs render as red, where the left leg is a mirror image of the right legs texture.
Expected Results: Left leg should be blue, right leg should be red.
Screenshots/Videos attached: Yes
Notes:

Steve model renders as expected.