Update TrelloJsonService.php

Fixes the following issue: nextcloud#5136
By fixing the following error when running 'php occ deck:import --system=TrelloJson'

Error: Call to a member function getUID() on string in /home/sites/site100028002/web/nextcloud.enklaave.org/apps/deck/lib/Service/Importer/Systems/TrelloJsonService.php:136

and 

Error: Call to a member function getUID() on string in /home/sites/site100028002/web/nextcloud.enklaave.org/apps/deck/lib/Service/Importer/Systems/TrelloJsonService.php:364


Signed-off-by: mulles <com.github@emu.lu>

lib/Service/Importer/Systems/TrelloJsonService.php

@@ -116,7 +116,7 @@ function (\stdClass $a) use ($trelloCard) {
 				$cardId = $this->cards[$trelloCard->id]->getId();
 				$comment = new Comment();
 				if (!empty($this->getImportService()->getConfig('uidRelation')->{$trelloComment->memberCreator->username})) {
-					$actor = $this->getImportService()->getConfig('uidRelation')->{$trelloComment->memberCreator->username}->getUID();
+					$actor = $this->getImportService()->getConfig('uidRelation')->{$trelloComment->memberCreator->username};
 				} else {
 					$actor = $this->getImportService()->getConfig('owner')->getUID();
 				}
@@ -344,7 +344,7 @@ private function translateColor(?string $color): string {
 
 	private function replaceUsernames(string $text): string {
 		foreach ($this->getImportService()->getConfig('uidRelation') as $trello => $nextcloud) {
-			$text = str_replace($trello, $nextcloud->getUID(), $text);
+			$text = str_replace($trello, $nextcloud, $text); 
 		}
 		return $text;
 	}