Add user session information to auth_hash

[theundeadmonk]

The Shopify Omniauth2 gem selectively wraps the parameters it receives into a custom Hash object. It discards all parameters that are not specified as part of the strategy.

Since we now pass a user session along with per-user tokens, we need to ensure that the auth hash object constructed by the gem has the session information.

This PR adds the session to the auth hash.

[theundeadmonk]

[theundeadmonk]

[ashchristopher]

🎉

[wnm]

Hi @theundeadmonk, do you know if the session in the auth hash is supposed to be the same, as the session which is passed as a parameter when opening an app from a store's app dashboard (mystore.com/admin/apps)?

There is an issue in the shopify_app gem related to this: Shopify/shopify_app#1181

[theundeadmonk]

Yes