add test case for csv BOM handling

spec/fixtures/csv/discourse.csv

@@ -1 +1,5 @@
-jeff@gmail.com,discourse;ubuntu,100
sam@yahoo.com,ubuntu,
robin@outlook.com,discourse,200
neil@aol.com,random,
regis@live.com,,8888
+jeff@gmail.com,discourse;ubuntu,100
+sam@yahoo.com,ubuntu,
+robin@outlook.com,discourse,200
+neil@aol.com,random,
+regis@live.com,,8888

spec/jobs/bulk_invite_spec.rb

@@ -18,6 +18,7 @@ describe Jobs::BulkInvite do
         bulk_invite.current_user = user
         bulk_invite.read_csv_file(csv_file)
         expect(Invite.where(email: "robin@outlook.com").exists?).to eq(true)
+        expect(Invite.where(email: "jeff@gmail.com").exists?).to eq(true) # handles BOM
       end
     end