Put the summary of the bug you're having here

What I expected to happen was the dog should just stay in sitting position:
Describe what you thought should happen here

What actually happened was when right clicked to sit on a slime block, it will glitch sit-stand-sit-stand-sit-stand until told to stand again or pushed off the slime block:
Describe what happened here

Steps to Reproduce:
1. place some slime blocks
2. spawn a wolf
3. tame it and make it sit on a slime block (it happened on a super flat world for me.)