Attempt to avoid a commit request that does not return for an extended time

[marblestation]

When we rebuild and we make the last commit, we are suffering problems such as:

Traceback (most recent call last):
  File \"scripts/reindex.py\", line 100, in run
    r = requests.get(update_url + '?commit=true')
  File \"/usr/local/lib/python3.8/dist-packages/requests/api.py\", line 75, in get
    return request('get', url, params=params, **kwargs)
  File \"/usr/local/lib/python3.8/dist-packages/requests/api.py\", line 60, in request
    return session.request(method=method, url=url, **kwargs)
  File \"/usr/local/lib/python3.8/dist-packages/requests/sessions.py\", line 524, in request
    resp = self.send(prep, **send_kwargs)
  File \"/usr/local/lib/python3.8/dist-packages/requests/sessions.py\", line 637, in send
    r = adapter.send(request, **kwargs)
  File \"/usr/local/lib/python3.8/dist-packages/requests/adapters.py\", line 498, in send
    raise ConnectionError(err, request=request)
requests.exceptions.ConnectionError: ('Connection aborted.', RemoteDisconnected('Remote end closed connection without response'))"

Solr documentation says default is "true" for waitSearcher (see https://solr.apache.org/guide/7_4/uploading-data-with-index-handlers.html)