Remove declaration of unthrown exception

Change-Id: I10045d56601cb1fb855fb4fbb5208fc47961b383
diff --git a/src/main/java/com/googlesource/gerrit/plugins/serviceuser/CreateServiceUserNotes.java b/src/main/java/com/googlesource/gerrit/plugins/serviceuser/CreateServiceUserNotes.java
index ba3f099..e1af041 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/serviceuser/CreateServiceUserNotes.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/serviceuser/CreateServiceUserNotes.java
@@ -27,7 +27,6 @@
 import com.google.inject.assistedinject.Assisted;
 import com.googlesource.gerrit.plugins.serviceuser.GetServiceUser.ServiceUserInfo;
 import java.io.IOException;
-import org.eclipse.jgit.api.errors.ConcurrentRefUpdateException;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
@@ -108,7 +107,7 @@
     }
   }
 
-  void commitNotes() throws IOException, ConcurrentRefUpdateException {
+  void commitNotes() throws IOException {
     try {
       if (serviceUserNotes == null) {
         return;
diff --git a/src/main/java/com/googlesource/gerrit/plugins/serviceuser/RefUpdateListener.java b/src/main/java/com/googlesource/gerrit/plugins/serviceuser/RefUpdateListener.java
index 29ab47b..bcf4c6b 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/serviceuser/RefUpdateListener.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/serviceuser/RefUpdateListener.java
@@ -26,7 +26,6 @@
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.io.IOException;
-import org.eclipse.jgit.api.errors.ConcurrentRefUpdateException;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.Repository;
@@ -107,7 +106,7 @@
           ObjectId.fromString(e.getOldObjectId()),
           ObjectId.fromString(e.getNewObjectId()));
       crn.commitNotes();
-    } catch (IOException | OrmException | ConfigInvalidException | ConcurrentRefUpdateException x) {
+    } catch (IOException | OrmException | ConfigInvalidException x) {
       log.error(x.getMessage(), x);
     }
   }