Minor, fix one more Actor -> Acting As PHID

Summary: See D10221, I missed one of these callsites.

Auditors: btrahan

src/applications/maniphest/editor/ManiphestTransactionEditor.php

@@ -380,6 +380,7 @@ final class ManiphestTransactionEditor
 
           id(new ManiphestTransactionEditor())
             ->setActor($this->getActor())
+            ->setActingAsPHID($this->getActingAsPHID())
             ->setContentSource($this->getContentSource())
             ->setContinueOnNoEffect(true)
             ->setContinueOnMissingFields(true)