- fixed schema uri

sigprops_retrofilm_video.xml

 <?xml version="1.0" encoding="UTF-8"?>
-<Object xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
- xsi:schemaLocation="http://slubarchiv.slub-dresden.de/sigprops1 ../../Downloads/sigprops.xsd"
- xmlns="http://slubarchiv.slub-dresden.de/sigprops1"><Metadata><CreationDate>2021-02-17T13:15:04</CreationDate><Creator>Andreas Romeyke</Creator><WorkflowName>Mediathek / SAVE</WorkflowName><InstitutionName>SLUB Dresden</InstitutionName><InstitutionContact>andreas.romeyke@slub-dresden.de</InstitutionContact><ObjectType>Retrodigitalisat (Film 8mm-35mm)</ObjectType></Metadata>
+<Object xmlns="http://slubarchiv.slub-dresden.de/sigprops1"
+    xsi:schemaLocation="http://slubarchiv.slub-dresden.de/sigprops1 https://slubarchiv.slub-dresden.de/slubarchiv/standards/sigprops/sigprops.xsd"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+    <Metadata>
+    <CreationDate>2021-02-17T13:15:04</CreationDate>
+    <Creator>Andreas Romeyke</Creator><WorkflowName>Mediathek / SAVE</WorkflowName><InstitutionName>SLUB Dresden</InstitutionName><InstitutionContact>andreas.romeyke@slub-dresden.de</InstitutionContact><ObjectType>Retrodigitalisat (Film 8mm-35mm)</ObjectType></Metadata>
     <SignificantProperties>
         <SignificantProperty>
             <PropertyName>viewable</PropertyName>