Some minor 3.0 fixes

[aldeed]

Resolves #4961
Resolves #5796
Resolves #4813
Impact: minor
Type: feature|bugfix

Issues

• approveOrderPayments mutation could not be called internally by plugins syncing from another system
• Shop resolvers for fields that return connections did not work (see Graphql requests which return Shop fail if requesting any of these fields: administrators, groups, roles, and tags.  #4961)
• Products slugs do not necessary have to be unique among all shops, but the catalogItemProduct GraphQL query did not accept a shopId for disambiguation.
• In the GraphQL schemas and SimpleSchema, the defaultParcelSize fields were required but they shouldn't be

Solution

• approveOrderPayments supports isInternalCall
• Shop resolvers for fields that return connections work properly
• The catalogItemProduct GraphQL query accepts an optional shopId argument that is recommended when looking up by slug
• You can now set one defaultParcelSize field without needing to set the others

Breaking changes

None

Testing

Verify the described fixes. For the shop resolvers one, use this query with an admin token:

{
  primaryShop {
    _id
    name
    administrators {
      nodes {
        name
      }
    }
    tags {
      nodes {
        name
      }
    }
    roles {
      nodes {
        name
      }
    }
    groups {
      nodes {
        name
      }
    }
  }
}

[willopez]

LGTM