Mining Fatigue slows down mining speed of instantly-mineable blocks when holding down left-click

If a player with Mining Fatigue mines an instantly-mineable block by holding down left-click, the block is not mined instantly.

Steps to Reproduce:

1. Place an instantly-mineable block such as grass in a line
2. Type /effect @s mining_fatigue 9999 1 true in the chat
3. Switch to Survival mode
4. Mine the grass by holding down left-click

Observed Results:
The grass is not mined instantly and shows cracks.

Expected Results:
It should be mined instantly.

Videos:
Holding down left-click:
Minecraft 2022-02-03 11-51-31.mp4

Tapping left-click:
Minecraft 2022-02-03 11-52-40.mp4