Fix broken repositories_spec test for creating new tags.

spec/requests/api/repositories_spec.rb

@@ -27,12 +27,10 @@ describe API::API, api: true  do
     it 'should create a new tag' do
       post api("/projects/#{project.id}/repository/tags", user),
            tag_name: 'v1.0.0',
-           ref: '621491c677087aa243f165eab467bfdfbee00be1'
+           ref: 'master'
       response.status.should == 201
-      json_response.first['name'].should == 'v1.0.0'
-      json_response['commit']['id'].should ==
-        '621491c677087aa243f165eab467bfdfbee00be1'
+      json_response['name'].should == 'v1.0.0'
     end
     it 'should deny for user without push access' do
       post api("/projects/#{project.id}/repository/tags", user2),