Update 'workshop_stream.sh'

workshop_stream.sh

@@ -1,13 +1,13 @@
 ./merge_scans.sh
-mkdir split
+mkdir -p split
 python3 burstpdf.py
-mkdir rotated
+mkdir -p rotated
 python3 rotation.py
-mkdir bounding_box
+mkdir -p bounding_box
 python3 bounding_box.py
-mkdir cropped
+mkdir -p cropped
 # python3 mirror_crop.py
-mkdir ocred
+mkdir -p ocred
 python3 tesseract_ocr.py
 ./remove.sh
 ./merge_files.sh