Tests/admin/wpCommentsListTable: split the original test class and adjust covers notation

[himanshupathak95]

Trac ticket: https://core.trac.wordpress.org/ticket/65208

Splits the existing test class Tests_Admin_wpCommentsListTable into five focused test classes, one per method under test:

• Admin_WpCommentsListTable_ExtraTablenav_Test - covers WP_Comments_List_Table::extra_tablenav
• Admin_WpCommentsListTable_BulkActions_Test - covers WP_Comments_List_Table::bulk_actions
• Admin_WpCommentsListTable_PrintColumnHeaders_Test - covers WP_Comments_List_Table::print_column_headers
• Admin_WpCommentsListTable_GetViews_Test - covers WP_Comments_List_Table::get_views
• Admin_WpCommentsListTable_PrepareItems_Test - covers WP_Comments_List_Table::prepare_items

The @covers annotation is moved from method-level (repeated on each test) to a single class-level declaration in each new class. This makes all classes compatible with PHPUnit 11.

No abstract TestCase base class was introduced since the shared set_up() is a single line. The PrintColumnHeaders class constructs its own mock directly and needs no set_up() at all.

Use of AI Tools

Used AI to debug test failures and refactor issues.

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