add doc example for imshow binary_backend_kwargs

Signed-off-by: maximsmol <[email protected]>

doc/python/imshow.md

@@ -74,6 +74,19 @@ fig = px.imshow(img, binary_format="jpeg", binary_compression_level=0)
 fig.show()
 ```
 
+```python
+import plotly.express as px
+from skimage import data
+img = data.astronaut()
+fig = px.imshow(
+  img,
+  # Pillow backend parameters are documented here: https://pillow.readthedocs.io/en/stable/handbook/image-file-formats.html#webp
+  # Available parameters depend on the `binary_format`
+  binary_backend_kwargs={"lossless": False}
+)
+fig.show()
+```
+
 ### Display single-channel 2D data as a heatmap
 
 For a 2D image, `px.imshow` uses a colorscale to map scalar data to colors. The default colorscale is the one of the active template (see [the tutorial on templates](/python/templates/)).