🐛 sbb_textline_detector: Do not print PAGE output to stdout

ocrd-sbb-textline-detector uses ocrd_page's parse() to parse XML input,
which writes the XML to stdout by default.

Fix this by silencing it using parse()'s silence=True.

qurator/sbb_textline_detector/ocrd_cli.py

@@ -72,7 +72,7 @@ class OcrdSbbTextlineDetectorRecognize(Processor):
 
                 # Read segmentation results
                 tmp_filename = os.path.join(tmp_dirname, file_id) + '.xml'
-                tmp_pcgts = ocrd_models.ocrd_page.parse(tmp_filename)
+                tmp_pcgts = ocrd_models.ocrd_page.parse(tmp_filename, silence=True)
                 tmp_page = tmp_pcgts.get_Page()
 
             # Create a new PAGE file from the input file