FEATURE: add website field to SSO

spec/models/discourse_single_sign_on_spec.rb

@@ -30,6 +30,7 @@ describe DiscourseSingleSignOn do
     sso.title = "user title"
     sso.custom_fields["a"] = "Aa"
     sso.custom_fields["b.b"] = "B.b"
+    sso.website = "https://www.discourse.org/"
     sso
   end
 
@@ -49,6 +50,7 @@ describe DiscourseSingleSignOn do
     expect(parsed.title).to eq sso.title
     expect(parsed.custom_fields["a"]).to eq "Aa"
     expect(parsed.custom_fields["b.b"]).to eq "B.b"
+    expect(parsed.website).to eq sso.website
   end
 
   it "can do round trip parsing correctly" do