minor #12720 Changed names of Intl classes in form types docs (jzawadzki)

This PR was submitted for the 5.0 branch but it was merged into the 4.3 branch instead (closes #12720).

Discussion
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Changed names of Intl classes in form types docs

As per symfony/symfony#28846 we changed Intl classes to be more specific. Looks like some docs left with old naming.

Commits
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f5f64e1 Changed names of Intl classes in form types docs

Author: OskarStark

reference/forms/types/country.rst

@@ -70,7 +70,7 @@ Overridden Options
 choices
 ~~~~~~~
 
-**default**: ``Symfony\Component\Intl\Intl::getRegionBundle()->getCountryNames()``
+**default**: ``Symfony\Component\Intl\Countries::getNames()``
 
 The country type defaults the ``choices`` option to the whole list of countries.
 The locale is used to translate the countries names.

reference/forms/types/currency.rst

@@ -62,7 +62,7 @@ Overridden Options
 choices
 ~~~~~~~
 
-**default**: ``Symfony\Component\Intl\Intl::getCurrencyBundle()->getCurrencyNames()``
+**default**: ``Symfony\Component\Intl\Currencies::getNames()``
 
 The choices option defaults to all currencies.
 

reference/forms/types/language.rst

@@ -72,7 +72,7 @@ Overridden Options
 choices
 ~~~~~~~
 
-**default**: ``Symfony\Component\Intl\Intl::getLanguageBundle()->getLanguageNames()``.
+**default**: ``Symfony\Component\Intl\Languages::getNames()``.
 
 The choices option defaults to all languages.
 The default locale is used to translate the languages names.

reference/forms/types/locale.rst

@@ -73,7 +73,7 @@ Overridden Options
 choices
 ~~~~~~~
 
-**default**: ``Symfony\Component\Intl\Intl::getLocaleBundle()->getLocaleNames()``
+**default**: ``Symfony\Component\Intl\Locales::getNames()``
 
 The choices option defaults to all locales. It uses the default locale to
 specify the language.