[Sync-EN] Fix outdated ReflectionClass::setStaticPropertyValue visibility handling

[lacatoire]

Syncs the RU page with php/doc-en#5057.

• refpurpose and the description no longer claim the method only sets public static properties: it sets a static property regardless of visibility.
• The second paragraph now presents ReflectionProperty::setValue as an alternative for static properties instead of listing visibilities.
• Changelog row: 7.4.0 becomes 7.4.9, 8.0.0, and the entry is reversed (private and protected static properties can now be set, a ReflectionException was thrown before). classname becomes exceptionname to match EN.
• EN-Revision bumped to c74adac363c4ad18bfb648b8962663b26de3828b.

Fixes: #1725