check_font() fstring update (#9208)

Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>

Signed-off-by: Glenn Jocher <glenn.jocher@ultralytics.com>

utils/general.py

@@ -456,7 +456,7 @@ def check_font(font=FONT, progress=False):
     font = Path(font)
     file = CONFIG_DIR / font.name
     if not font.exists() and not file.exists():
-        url = "https://ultralytics.com/assets/" + font.name
+        url = f'https://ultralytics.com/assets/{font.name}'
         LOGGER.info(f'Downloading {url} to {file}...')
         torch.hub.download_url_to_file(url, str(file), progress=progress)