As part of WT-12657, the checkpoint cleanup utility thread is added to perform the checkpoint cleanup instead of the checkpoint operation itself.

/* Open a handle for processing. */
    ret = __wt_session_get_dhandle(session, uri->data, NULL, NULL, 0);
    if (ret != 0)
        WT_RET_MSG(session, ret, "%s: unable to open handle%s", (char *)uri->data,
          ret == EBUSY ? ", error indicates handle is unavailable due to concurrent use" : "");

It reports an error message into the mongod.log file whenever it fails to acquire the dhandle. This is causing problems for some applications, and we are treating that as an error. Change the error message into a verbose message.