[php-src] Issue #8478: PHP 8.0 tests must be compatible /w MySQL 8.0

Issue: https://github.com/php/php-src/issues/8478 Author: mvorisek ### Description see https://github.com/php/php-src/runs/6250284285?check_suite_focus=true#step:8:4209 ``` Fetching results from tables of different charsets. [D:\a\php-src\php-src\ext\mysqli\tests\mysqli_character_set.phpt] mysqli_options() [D:\a\php-src\php-src\ext\mysqli\tests\mysqli_options.phpt] mysqli_set_charset() [D:\a\php-src\php-src\ext\mysqli\tests\mysqli_set_charset.phpt] PDO ODBC "long" columns [D:\a\php-src\php-src\ext\pdo_odbc\tests\long_columns.phpt] MySQL PDO->__construct() - URI [D:\a\php-src\php-src\ext\pdo_mysql\tests\pdo_mysql___construct_uri.phpt] ``` the last test will be fixed by https://github.com/php/php-src/pull/8451 can someone advise how to fix these tests to be working /w MySQL 8.0? ### PHP Version PHP 8.0.x, maybe also higher ### Operating System linux