Merge pull request '#290 Egon exporter file name' (#291) from 290_EGON_Exporter_file_name into master

Reviewed-on: SGD-Nord/konova#291

intervention/utils/egon_export.py

@@ -152,7 +152,7 @@ class EgonGmlBuilder:
                     "oneo:aufnahmezeitpunkt": doc.date_of_creation.strftime(DEFAULT_DATE_FORMAT),
                     "oneo:bemerkung": doc.comment,
                     "oneo:fotoverweis": base64.b64encode(doc.file.read()).decode("utf-8"),
-                    "oneo:dateiname": doc.title,
+                    "oneo:dateiname": doc.file.url.split("/")[-1],
                     "oneo:hauptfoto": False,
                 }
             } for doc in regular_docs