Fixes deprecation warning:
```
DEPRECATION WARNING: The success? predicate is deprecated and
will be removed in Rails 6.0.
Please use successful? as provided by Rack::Response::Helpers.
```
This moves all existing `image/services/before_script/variables`
into `default:`. This allows us to easily add a default and
top-level entries. `default`: is keep backward compatible: to
be considered to be job if `default:script:` is specified. This
behavior should be removed.
All existing `image/services/before_script/variables` are properly
handled in root context.
Gitlab::HTTP now resolves the hostname only once, verifies the IP is not
blocked, and then uses the same IP to perform the actual request, while
passing the original hostname in the `Host` header and SSL SNI field.
Updates specs to use new rails5 format.
The old format:
`get :show, { some: params }, { some: headers }`
The new format:
`get :show, params: { some: params }, headers: { some: headers }`
