Fix attr assignment in OAuth::RateLimitExceeded (#547)

Author: nnc

lib/xeroizer/oauth.rb

@@ -37,7 +37,7 @@ def initialize(description, retry_after: nil, daily_limit_remaining: nil)
         super(description)
 
         @retry_after = retry_after
-        @daily_limit_remaining = @daily_limit_remaining
+        @daily_limit_remaining = daily_limit_remaining
       end
 
       attr_reader :retry_after, :daily_limit_remaining

test/unit/http_test.rb

@@ -180,6 +180,8 @@ class HttpTest < UnitTestCase
           assert_match /rate limit exceeded/i, error.message
           assert_match /328 requests left for the day/i, error.message
           assert_match /42 seconds until you can make another request/i, error.message
+          assert_equal 42, error.retry_after
+          assert_equal 328, error.daily_limit_remaining
         end
       end
     end