adds connection timeout to job submitter

[sv3ndk]

Hi all,

While experimenting with the Flink operator, I experienced some occasional glitches when the very first curl done by the job submitter hangs for a very long time before retrying, instead of the usual 5 seconds. It then eventually times out, although this long pause has an unnecessary impact on the deployment duration.

Checking job manager to be ready. Will check success of 2 API calls for stable job submission.
curl -sS "http://fandom-analytics-metrics-computer-jobmanager:8081/jobs"

I believe this happens when the job submitter calls curl before the job manager is even started, in which case we're getting connection timeout (after 120s) instead of an immediate "connection refused".

After adding the --connect-timeout 5, all deployment continued to work successfully, and I never experienced again the hanging behaviour mentioned above.

Let me know your thoughts

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[sv3ndk]

@googlebot I signed it!

[sv3ndk]

@hongyegong , could you please have a quick look at this minor update and let me know what you think? Thanks