Bug 925850 - Modify the test_dialer_make_call assertion to handle long phone numbers

Hi!
I added a check here. The regular size of a phone number is 12 characters ("+4" followed by the phone number, which has 10 digits). If the phone number has more than 12 characters, which is the case of UK (13 characters - "+4" followed by 11 digits phone number), then we eliminate "+4" from the assertion and only check the 11 digits phone number.