[tests] make token_signer-itest more robust

This patch updates the scenarios of the token_signer-itest to pass when
run at very busy/overloaded nodes and at nodes with a slow or
misconfigured DNS resolver.

Change-Id: I8cb3a5d3ca42546073370be42459f4f03dd725cb
Reviewed-on: http://gerrit.cloudera.org:8080/21022
Reviewed-by: Ádám Bakai <abakai@cloudera.com>
Tested-by: Alexey Serbin <alexey@apache.org>
Reviewed-by: Abhishek Chennaka <achennaka@cloudera.com>
1 file changed