Update Set-ArcConfig.md

Author: supermistag

exchange/exchange-ps/exchange/Set-ArcConfig.md

@@ -92,7 +92,7 @@ else {
 
 This examples removes a specific ARC sealer from the list. If, after removing this entry from the list, no other ARC Sealers exist, using the " " works around the below error if $DomainsToRemove is empty 
 
-```
+```yaml
 (Cannot bind argument to parameter 'ArcTrustedSealers' because it is an empty array.)
 ```