Hello,
Max answer focuses on the CLI. Instead, using the Community Edition Platform, proceed as follows:
# You must first delete all files in your folder.
1. import org.apache.hadoop.fs.{Path, FileSystem}
2. dbutils.fs.rm("/FileStore/tables/file.csv")
You can refresh DBFS each time you proceed to action above for checking is the file was deleted.
When all files are deleted then you can delete the folder using the same command (2.).
Good luck.