Error creating tmp dir with no-stream and relative paths

[johnlees]

e.g. run with --no-stream --ref-db ../query_db
Will fail with:

  File "PopPUNK/mash.py", line 462, in queryDatabase
    suffix=".tmp", dir="./" + os.path.basename(dbPrefix))
  File "tempfile.py", line 340, in mkstemp
    return _mkstemp_inner(dir, prefix, suffix, flags, output_type)
  File "tempfile.py", line 258, in _mkstemp_inner
    fd = _os.open(file, flags, 0o600)
FileNotFoundError: [Errno 2] No such file or directory: './query_db/query_dby6aic3ql.tmp'

Need to fix lines:

    if no_stream:
            tmpHandle, tmpName = mkstemp(prefix=os.path.basename(dbPrefix),
                                         suffix=".tmp", dir="./" + os.path.basename(dbPrefix))
            mash_cmd += " > " + tmpName