Move en-US.yml's cell_phone entry to the correct position

`PhoneNumber.cell_phone` expects an i18n key of `cell_phone.formats`,
but the en-US.yml file currently has `faker.phone_number.cell_phone`
instead of `faker.cell_phone`.

The result of that mismatch is that `cell_phone` will ignore the defined
formats, and potentially generate invalid US numbers (e.g. those with an
area code beginning with 1) when the locale is en-US.

31d99d1 reworked YAML structure and
appears to have inadvertently moved the key.

You can see the change in US number behavior in a console:

  Faker::Config.locale = "en-US"
  Faker::PhoneNumber.translate("faker.cell_phone.formats")

On 3.3.0 this returns

  ["###-###-####", "(###) ###-####", "###.###.####", "### ### ####"]

because it's the fallback value within the `en` (not `en-US`) locale
file. The correct value should be the formats outdented in this commit.

lib/locales/en-US.yml

@@ -6949,16 +6949,16 @@ en-US:
         - "(#{PhoneNumber.area_code}) #{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number} x#{PhoneNumber.extension}"
         - "#{PhoneNumber.area_code}-#{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number} x#{PhoneNumber.extension}"
         - "#{PhoneNumber.area_code}.#{PhoneNumber.exchange_code}.#{PhoneNumber.subscriber_number} x#{PhoneNumber.extension}"
-      cell_phone:
-        formats:
-          - "#{PhoneNumber.area_code}-#{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number}"
-          - "(#{PhoneNumber.area_code}) #{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number}"
-          - "#{PhoneNumber.area_code}-#{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number}"
-          - "#{PhoneNumber.area_code}.#{PhoneNumber.exchange_code}.#{PhoneNumber.subscriber_number}"
-          - "#{PhoneNumber.area_code}-#{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number}"
-          - "(#{PhoneNumber.area_code}) #{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number}"
-          - "#{PhoneNumber.area_code}-#{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number}"
-          - "#{PhoneNumber.area_code}.#{PhoneNumber.exchange_code}.#{PhoneNumber.subscriber_number}"
+    cell_phone:
+      formats:
+        - "#{PhoneNumber.area_code}-#{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number}"
+        - "(#{PhoneNumber.area_code}) #{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number}"
+        - "#{PhoneNumber.area_code}-#{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number}"
+        - "#{PhoneNumber.area_code}.#{PhoneNumber.exchange_code}.#{PhoneNumber.subscriber_number}"
+        - "#{PhoneNumber.area_code}-#{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number}"
+        - "(#{PhoneNumber.area_code}) #{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number}"
+        - "#{PhoneNumber.area_code}-#{PhoneNumber.exchange_code}-#{PhoneNumber.subscriber_number}"
+        - "#{PhoneNumber.area_code}.#{PhoneNumber.exchange_code}.#{PhoneNumber.subscriber_number}"
     id_number:
       valid: "#{IdNumber.ssn_valid}"
       invalid:

test/test_en_us_locale.rb

@@ -46,6 +46,13 @@ def test_validity_of_phone_method_output
     assert_match(us_number_validation_regex, Faker::PhoneNumber.phone_number)
   end
 
+  def test_en_us_specific_phone_formats
+    en_translations = I18n.translate('faker.cell_phone.formats', locale: :en, raise: true)
+    en_us_translations = I18n.translate('faker.cell_phone.formats', locale: Faker::Config.locale, raise: true)
+
+    refute_equal en_translations, en_us_translations
+  end
+
   def test_en_us_invalid_state_raises_exception
     assert_raise(I18n::MissingTranslationData) { Faker::Address.zip_code(state_abbreviation: 'NA') }
   end