Remove unused imports

Change-Id: I40b4bb69354734e0b74890aa626321dadc4344ed
diff --git a/src/main/java/com/googlesource/gerrit/plugins/serviceuser/ServiceUserResolver.java b/src/main/java/com/googlesource/gerrit/plugins/serviceuser/ServiceUserResolver.java
index 188692d..fd360cc 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/serviceuser/ServiceUserResolver.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/serviceuser/ServiceUserResolver.java
@@ -18,7 +18,6 @@
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.reviewdb.client.Account;
 import com.google.gerrit.reviewdb.client.AccountGroup;
-import com.google.gerrit.reviewdb.client.Change.Id;
 import com.google.gerrit.reviewdb.server.ReviewDb;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.IdentifiedUser;
@@ -40,7 +39,6 @@
 import org.eclipse.jgit.lib.PersonIdent;
 
 import java.util.ArrayList;
-import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
 import java.util.Set;