The twitter gem now requires a proper Content-Type

spec/models/agents/twitter_favorites_spec.rb

@@ -4,6 +4,7 @@ describe Agents::TwitterFavorites do
   before do
     stub_request(:any, /tectonic.*[?&]tweet_mode=extended/).
       to_return(body: File.read(Rails.root.join("spec/data_fixtures/user_fav_tweets.json")),
+                headers: { 'Content-Type': 'application/json;charset=utf-8' },
                 status: 200)
   end
 

spec/models/agents/twitter_search_agent_spec.rb

@@ -5,7 +5,9 @@ describe Agents::TwitterSearchAgent do
     # intercept the twitter API request
     stub_request(:any, /freebandnames.*[?&]tweet_mode=extended/).
       to_return(body: File.read(Rails.root.join("spec/data_fixtures/search_tweets.json")),
+                headers: { 'Content-Type': 'application/json;charset=utf-8' },
                 status: 200)
+
     @opts = {
       search: "freebandnames",
       expected_update_period_in_days: "2",

spec/models/agents/twitter_user_agent_spec.rb

@@ -5,6 +5,7 @@ describe Agents::TwitterUserAgent do
     # intercept the twitter API request for @tectonic's user profile
     stub_request(:any, "https://api.twitter.com/1.1/statuses/user_timeline.json?contributor_details=true&count=200&exclude_replies=false&include_entities=true&include_rts=true&screen_name=tectonic&tweet_mode=extended").
       to_return(body: File.read(Rails.root.join("spec/data_fixtures/user_tweets.json")),
+                headers: { 'Content-Type': 'application/json;charset=utf-8' },
                 status: 200)
 
     @opts = {