apply given API service client options

[AlexanderZagaynov]

That feature was broken with Google's gem update and
this PR: 5ec9a15#diff-c6b2ed334d1938d66b4e168f255abbb7L140

Now it's back.

[houndci-bot]

Naming/UncommunicativeMethodParamName: Method parameter must be at least 3 characters long.

[Temikus]

@AlexanderZagaynov Thank you very much for the contribution!

LGTM overall. If integration tests pass I'll try to merge this with 1.8.0 I'm planning to release anyway.

[AlexanderZagaynov]

@Temikus About testing - can you please give me a hint where to put those tests?
I found nothing similar in existing code.
As I understood, codecov want me to cover

fog-google/lib/fog/google/shared.rb

Line 129 in 42b8df5

def apply_client_options(service, google_client_options: nil, **_ignored)

But I have no idea about proper way to do that.

[Temikus]

@AlexanderZagaynov I don't think we have a reasonable module to test Shared yet, so I'll write one.

Only thing I ask is - can you please give me a couple of examples of common use-cases? There are a lot of options so I want to be sure we're testing the right thing.

[AlexanderZagaynov]

@Temikus we're going to use that in a way like:

conn = Fog::Compute::Google.new(google_client_options: { proxy_url: 'https://user:password@host:8080' })
conn.list_servers('')

it should give ArgumentError: unsupported proxy
without proxy_url it should simply try to connect (returns Invalid request in example above).
old PR was here: #154

[Temikus]

@AlexanderZagaynov Thanks for the contribution, I've added a small test for it. It's not ideal but should cover at least a part of the risk surface.