[BUG] Unique filenames are not generated when drawing labels

[ehofesmann]

When drawing labels on samples and saving them to disk, it is expected that unique filenames will be created if multiple samples in the view have the same filename/path. However, currently these unique filenames aren't generated and only one copy of each file will be written.

from fiftyone import ViewField as F
import fiftyone.zoo as foz

dataset = foz.load_zoo_dataset("quickstart").clone()
sample = dataset.first()
dataset.add_sample(sample)

dup_view = dataset.match(F("filepath") == sample.filepath)
dup_view.draw_labels("/tmp/draw-labels", label_fields=["ground_truth"])

Resulting directory:

/tmp/draw-labels
    00880.jpg

Expected result:

/tmp/draw-labels
    00880.jpg
    00880-2.jpg