Show warning for non-NTFS file system on Windows clients

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## Feature request

**Which Nextcloud Version are you currently using:**
Windows Desktop Client 3.12.8

**Is your feature request related to a problem? Please describe.**
Yesterday I had a frustrating evening because for every local file move between directories the Nextcloud client executed a "old location file delete" + "new location file upload". Today I found out that the reason is that my partition uses the exFAT file system which has "instable" FileIDs.

**Describe the solution you'd like**
Users should get a warning if they use Nextcloud on a local directory inside an exFAT or FAT32 (who knows) drive. The warning should inform them that not all features might work as expected, e.g. file move.

**Describe alternatives you've considered**
Fix the file move detection also for file systems where the FileId (I used `fsutil file queryfileid `) changes between folder moves.

**Additional context**
Actually I don't know why I've chosen exFAT back then when I set up my Nextcloud sync partition.
I replayed the scenario (file create, rename inside directory, move to subdirectory) with exFAT, FAT32 and NTFS on a blank USB drive. It behaved like described, only NTFS had a stable FileID.