FIX: unstable username when dinopark username taken

Taken usernames would change on every profile refresh.

https://github.com/mozilla/discourse/issues/183

lib/mozilla_iam/profile/update_username.rb

@@ -14,7 +14,7 @@ module MozillaIAM
       return if User.reserved_username? username
 
       if @user.username.downcase != username.downcase
-        username = UserNameSuggester.find_available_username_based_on(username)
+        username = UserNameSuggester.find_available_username_based_on(username, @user.username)
       end
 
       unless @user.change_username(username)

plugin.rb

@@ -1,6 +1,6 @@
 # name: mozilla-iam
 # about: A plugin to integrate Discourse with Mozilla's Identity and Access Management (IAM) system
-# version: 1.2.0-alpha.8
+# version: 1.2.0-alpha.9
 # authors: Leo McArdle
 # url: https://github.com/mozilla/discourse-mozilla-iam
 

spec/components/mozilla_iam/profile/update_username_spec.rb

@@ -48,6 +48,7 @@ describe MozillaIAM::Profile do
         Fabricate(:user, username: username_after)
         Fabricate(:user, username: "#{username_after}1")
         profile.send(:update_username)
+        profile.send(:update_username)
         user.reload
         expect(user.username).to_not eq username_before
         expect(user.username).to eq "#{username_after}2"
@@ -68,6 +69,7 @@ describe MozillaIAM::Profile do
           Fabricate(:user, username: "johnsmi#{n}")
         end
         profile.send(:update_username)
+        profile.send(:update_username)
         user.reload
         expect(user.username).to_not eq username_before
         expect(user.username).to eq "Johnsm10"