Fix bug for SessionStorage#with_shopify_session

[m11o]

What this PR does

ShopifyApp::SessionStorage#with_shopify_session is given proc instance in block argument now. But, it should call block and be supplied session instance (ShopifyAPI::Auth::Session) to block. So I modified it and wrote test.

How to use

shop = Shop.find_by shopify_domain: 'example.myshopify.com'
shop.with_shopify_session do |session|
  client = ShopifyAPI::Clients::Graphql::Admin.new(session: session)
  response = client.query(query: query)
end

Reviewer's guide to testing

Run following

bundle exec rake test TEST=test/shopify_app/session/session_storage_test.rb

Things to focus on

1. lib/shopify_app/session/session_storage.rb
2. test/shopify_app/session/session_storage_test.rb

Checklist

Before submitting the PR, please consider if any of the following are needed:

• Update CHANGELOG.md if the changes would impact users
• Update README.md, if appropriate.
• Update any relevant pages in /docs, if necessary
• For security fixes, the Disclosure Policy must be followed.

[m11o]

I've signed the CLA!

[yourivdlans]

Would be awesome to get this merged!

cc @andyw8 @teddyhwang @nelsonwittwer

[ElliottRoche]

Is this any closer to being merged? Could really use it in our app code that we're trying to upgrade. with_shopify_session is a super important and useful method for us and I'm sure a lot of other people.

[nelsonwittwer]

🤦 This sat open for way too long. This is the correct fix, thank you for providing it @m11o !! ❤️