Note: the folder disappears from Project Browser, but it stays on disc, so it is not data loss. If folder has some content in it (assets, subfolders) - all that will disappear from Project Browser and AssetDB doesn't see those assets any more (e.g Search doesn't find those assets).

How to reproduce:
1. Create a new Unity project
2. In the Project window, open the Assets folder
3. In the Assets folder create a new folder called "test.meta"
4. Observe the Assets folder and the Console

Actual result: The created folder disappears from Project Browser and errors are thrown
Expected result: The created folder is not disappear

Reproducible with: 2022.1.0a1, 6000.0.63f1, 6000.2.15f1, 6000.3.0f1, 6000.4.0a5, 6000.5.0a2

Reproducible on: Windows 11
Not reproducible on: No other environments tested

Notes:
- "YAML Parsing error 'Parser Failure at line 1: Expected non empty YAML buffer'" and "Invalid .meta file" errors are thrown
- "A meta data file (.meta) exists but its asset 'Assets/test' can't be found." warning is thrown