Fix unused imports in QueryShell

Change-Id: Ibb608428b9abe37d0331f4b8c9fa5ba333196690
diff --git a/gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/QueryShell.java b/gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/QueryShell.java
index d979745..3f0bc4c 100644
--- a/gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/QueryShell.java
+++ b/gerrit-sshd/src/main/java/com/google/gerrit/sshd/commands/QueryShell.java
@@ -16,11 +16,8 @@
 
 import com.google.gerrit.common.Version;
 import com.google.gerrit.reviewdb.server.ReviewDb;
-import com.google.gson.Gson;
 import com.google.gson.JsonArray;
-import com.google.gson.JsonElement;
 import com.google.gson.JsonObject;
-import com.google.gson.JsonParser;
 import com.google.gwtorm.jdbc.JdbcSchema;
 import com.google.gwtorm.server.OrmException;
 import com.google.gwtorm.server.SchemaFactory;