Replace all Pix.read with Pix.open

tests/test_lept.py

@@ -26,5 +26,5 @@ import ocrmypdf.leptonica as lept
 def test_colormap_backgroundnorm(resources):
     # Issue #262 - unclear how to reproduce exactly, so just ensure leptonica
     # can handle that case
-    pix = lept.Pix.read(resources / 'baiona-colormapped.png')
+    pix = lept.Pix.open(resources / 'baiona-colormapped.png')
     pix.background_norm()

tests/test_main.py

@@ -109,7 +109,7 @@ def test_deskew(spoof_tesseract_noop, resources, outdir):
         log=log,
         pageno=1)
 
-    pix = Pix.read(str(deskewed_png))
+    pix = Pix.open(deskewed_png)
     skew_angle, skew_confidence = pix.find_skew()
 
     print(skew_angle)