fix lint error

Author: casten

PiCowbell_Camera_Demos/JPEG_Capture/code.py

@@ -94,7 +94,7 @@ def open_next_image():
     except Exception:
         print(f"Quality {quality} was too big.  Trying next lowest.")
 
-if b==None:
+if b is None:
     print("There wasn't enough system memory to allocate the lowest quality buffer.")
 
 jpeg = cam.capture(b)