update http client version

[joshlarsen]

I see there is some discussion about changing the http client. In the mean time, perhaps we can bump the current client to a more recent version.

[cben]

Let's see, reading https://github.com/httprb/http/blob/master/CHANGES.md...

Have you tried running with 4.0?

[cben]

• Drop Ruby 2.2 support for (future) 4.x+ releases httprb/http#467 Drop Ruby 2.2 support
  kubeclient still supports 2.2 and later. Can we support both http versions with http >= 3.0?
  Ruby 2.2 and 2.3 are EOL, so I'm open to dropping 2.2 or both, but that can only happen in a major release.

[joshlarsen]

@cben I am running 4.1 and no issues so far. I agree http >= 3.0 seems like a good compromise to support both.

[cben]

• Simplify setting a timeout httprb/http#446

  The previous style: .timeout(:global|:per_operation, hash_of_options) doesn't work anymore.

  Not a problem, kubeclient only uses http gem for watch and deliberately doesn't set any timeouts.

Other 4.0.0 changes don't sound relevant.

[cben]

• Raise ConnectionError when writing to socket fails httprb/http#436 Raise ConnectionError when writing to socket fails (insdead of Errno::EPIPE or similar).

  At one point, kubeclient was catching Errno::EBADF but the scenario was different, not relevant.
  Also catch standard error when watch stream finished #315 changed it to catch StandardError which would cover HTTP::ConnectionError.

[cben]

Weird, the 2.2.0 job https://travis-ci.org/abonas/kubeclient/jobs/545301561#L488
said Installing http 4.0.0

[cben]

Aha, 4.0.0 metadata still declared 2.2 support.
Later rubies get Fetching http 4.1.1

[cben]

Asked on httprb/http@190d4eb