Random.phone sometimes generates an extra digit at the end of the phone number

[smoyte]

For example, see the following output:

irb(main):024:0> Random.phone
=> "235-306-5221"
irb(main):025:0> Random.phone
=> "924-824-7990"
irb(main):026:0> Random.phone
=> "396-991-3759"
irb(main):027:0> Random.phone
=> "738-483-5420"
irb(main):028:0> Random.phone
=> "735-520-8574"
irb(main):029:0> Random.phone
=> "856-690-3655"
irb(main):030:0> Random.phone
=> "480-373-1639"
irb(main):031:0> Random.phone
=> "152-216-7767"
irb(main):032:0> Random.phone
=> "278-245-7239"
irb(main):033:0> Random.phone
=> "631-627-10576"