fix a skimage->scikit-image that was missed earlier

Author: tobyhodges

episodes/02-image-basics.md

@@ -180,7 +180,7 @@ so you might be asking why we don't use it here.
 Actually, `skimage.io.imread()` uses `iio.imread()` internally when loading an image into Python.
 It is certainly something you may use as you see fit in your own code.
 In this lesson, we use the imageio library to read or write (save) images,
-while `skimage` is dedicated to performing operations on the images.
+while scikit-image is dedicated to performing operations on the images.
 Using imageio gives us more flexibility, especially when it comes to
 handling metadata.