drive: fix description being overwritten on server side moves

Before this the description for files got overwritten on server side
moves.

This change stops rclone setting the description to the leaf name
completely.

See: https://forum.rclone.org/t/file-descriptions-in-google-drive-not-shown-after-dedupe/45510
Fixes: #7770

backend/drive/drive.go

@@ -1747,10 +1747,9 @@ func (f *Fs) createDir(ctx context.Context, pathID, leaf string, metadata fs.Met
 	leaf = f.opt.Enc.FromStandardName(leaf)
 	pathID = actualID(pathID)
 	createInfo := &drive.File{
-		Name:        leaf,
-		Description: leaf,
-		MimeType:    driveFolderType,
-		Parents:     []string{pathID},
+		Name:     leaf,
+		MimeType: driveFolderType,
+		Parents:  []string{pathID},
 	}
 	var updateMetadata updateMetadataFn
 	if len(metadata) > 0 {
@@ -2430,7 +2429,6 @@ func (f *Fs) createFileInfo(ctx context.Context, remote string, modTime time.Tim
 	// Define the metadata for the file we are going to create.
 	createInfo := &drive.File{
 		Name:         leaf,
-		Description:  leaf,
 		Parents:      []string{directoryID},
 		ModifiedTime: modTime.Format(timeFormatOut),
 	}