A PHP warning is given when the SQL server is shutdown or restarted

Describe the bug

A PHP warning is given when the SQL server is shutdown or restarted, and a query was still executing.

To Reproduce

Steps to reproduce the behavior:

1. Execute a query that takes long enough.
2. Visit the login page in the same browser in a new tab.
3. Shutdown or restart the SQL server.
4. See error

Expected behavior

The warning shouldn't be given.

Screenshots

Server configuration

• Operating system: Windows
• Web server: nginx/1.19.8
• Database version: 5.7.32
• PHP version: 8.0.3
• phpMyAdmin version: 5.1.0

Client configuration

• Browser: Firefox
• Operating system: Windows

Additional context

Warning in .\libraries\classes\Dbal\DbiMysqli.php#244
mysqli::query(): (08S01/1053): Server shutdown in progress

Backtrace

.\libraries\classes\Dbal\DbiMysqli.php#244: mysqli->query(
string 'SELECT * FROM `tbl_users` WHERE `username` IS NOT NULL ',
integer 0,
)
.\libraries\classes\DatabaseInterface.php#213: PhpMyAdmin\Dbal\DbiMysqli->realQuery(
string 'SELECT * FROM `tbl_users` WHERE `username` IS NOT NULL ',
,
integer 0,
)
.\libraries\classes\Sql.php#817: PhpMyAdmin\DatabaseInterface->tryQuery(string 'SELECT * FROM `tbl_users` WHERE `username` IS NOT NULL ')
.\libraries\classes\Sql.php#907: PhpMyAdmin\Sql->countQueryResults(
integer 25,
boolean false,
string 'db_name',
string 'tbl_users',
array,
)
.\libraries\classes\Sql.php#1805: PhpMyAdmin\Sql->executeTheQuery(
array,
string 'SELECT * FROM `tbl_users` WHERE `username` IS NOT NULL LIMIT 0, 25 ',
boolean false,
string 'db_name',
string 'tbl_users',
NULL,
NULL,
NULL,
)
.\libraries\classes\Controllers\ImportController.php#816: PhpMyAdmin\Sql->executeQueryAndGetQueryResponse(
array,
boolean false,
string 'db_name',
string 'tbl_users',
NULL,
NULL,
NULL,
NULL,
NULL,
string 'index.php?route=/table/structure',
string './themes/pmahomme/img/',
NULL,
NULL,
string 'SELECT * FROM `tbl_users` WHERE `username` IS NOT NULL',
NULL,
)
.\libraries\classes\Routing.php#186: PhpMyAdmin\Controllers\ImportController->index(array)
.\index.php#18: PhpMyAdmin\Routing::callControllerForRoute(
string '/import',
,
,
)

Start with libraries/classes/Dbal/DbiMysqli.php at line 244, then follow the call through libraries/classes/DatabaseInterface.php and libraries/classes/Sql.php. Reproduce the long-running query and SQL-server restart described in the issue, and verify that the server-shutdown condition no longer produces a PHP warning.