Posts block - Posts are duplicate in display if you accidentally clicked the Load More button two or more times

[andeng1106]

Describe the bug If you accidentally clicked the Load More button two or more times:

• Posts are repeatedly displaying
• Posts from a different category appear (haven't encountered this yet but a user did)

To Reproduce Steps to reproduce the behavior:

1. Add a new page
2. Add a Posts block
3. In the post block, add a Load More button
4. Publish page or preview in new tab
5. Click the Load More button two or more times
6. Check if new posts that are loaded has been loaded already (duplicate)

Expected behavior When clicking the Load More button two or more times, it shouldn't load the next posts two or more times and should not duplicate.

Screenshots

https://user-images.githubusercontent.com/103395655/166899931-0dd95705-a6ca-46f6-9756-56da1ab2b78d.mp4