remove existing annotation below the line level to avoid inconsistency

ocrd_calamari/recognize.py

@@ -77,8 +77,14 @@ class CalamariRecognize(Processor):
                     line_text = prediction.sentence
                     line_conf = prediction.avg_char_probability
 
+                    if line.get_TextEquiv():
+                        log.warning("Line '%s' already contained text results", line.id)
                     line.set_TextEquiv([TextEquivType(Unicode=line_text, conf=line_conf)])
                     
+                    if line.get_Word():
+                        log.warning("Line '%s' already contained word segmentation", line.id)
+                    line.set_Word([])
+
             _page_update_higher_textequiv_levels('line', pcgts)
 
             file_id = self._make_file_id(input_file, n)