Merge pull request #1719 from nextcloud/stable9-backport-1580

[stable9] Unset user PHOTO before setting new one in OCA\DAV\CardDAV\Converter:…

apps/dav/lib/carddav/converter.php

@@ -92,6 +92,7 @@ class Converter {
 		}
 
 		if($this->propertyNeedsUpdate($vCard, 'PHOTO', $image)) {
+			unset($vCard->PHOTO);
 			$vCard->add('PHOTO', $image->data(), ['ENCODING' => 'b', 'TYPE' => $image->mimeType()]);
 			$updated = true;
 		}