make sure image is also imported when importing an image format

piet/Cargo.toml

@@ -21,18 +21,18 @@ samples = ["pico-args", "png", "os_info"]
 
 # passing on all the image features. AVIF is not supported because it does not
 # support decoding, and thats al we use `Image` for.
-image_png = ["image/png"]
-jpeg = ["image/jpeg"]
-jpeg_rayon = ["image/jpeg_rayon"]
-gif = ["image/gif"]
-bmp = ["image/bmp"]
-ico = ["image/ico"]
-tiff = ["image/tiff"]
-webp = ["image/webp"]
-pnm = ["image/pnm"]
-dds = ["image/dds"]
-tga = ["image/tga"]
-farbfeld = ["image/farbfeld"]
-dxt = ["image/dxt"]
-hdr = ["image/hdr"]
+image_png = ["image/png", image]
+jpeg = ["image/jpeg", image]
+jpeg_rayon = ["image/jpeg_rayon", image]
+gif = ["image/gif", image]
+bmp = ["image/bmp", image]
+ico = ["image/ico", image]
+tiff = ["image/tiff", image]
+webp = ["image/webp", image]
+pnm = ["image/pnm", image]
+dds = ["image/dds", image]
+tga = ["image/tga", image]
+farbfeld = ["image/farbfeld", image]
+dxt = ["image/dxt", image]
+hdr = ["image/hdr", image]