fix: Use mongosh instead of mongo command in entrypoint (#21010)

Some merge problem in the fix from
https://github.com/appsmithorg/appsmith/pull/20055 caused this line to
not get the change.

deploy/docker/entrypoint.sh

@@ -168,7 +168,7 @@ init_replica_set() {
     mongod --fork --port 27017 --dbpath "$MONGO_DB_PATH" --logpath "$MONGO_LOG_PATH" --replSet mr1 --keyFile /mongodb-key --bind_ip localhost
     echo "Waiting 10s for MongoDB to start with Replica Set"
     sleep 10
-    mongo "$APPSMITH_MONGODB_URI" --eval 'rs.initiate()'
+    mongosh "$APPSMITH_MONGODB_URI" --eval 'rs.initiate()'
     mongod --dbpath "$MONGO_DB_PATH" --shutdown || true
   fi