Add PHP 8.5 to the build matrix

[jakzal]

No description provided.

[jakzal]

PHP 8.5 build fails:

#95 1.160 ✘box-3
#95 1.160 
#95 1.160 Deprecated: {closure:Amp\Promise\wrap():574}(): Implicitly marking parameter $exception as nullable is deprecated, the explicit nullable type must be used instead in phar:///tools/.phive/phars/humbug/box-3.16.0.phar/vendor/amphp/amp/lib/functions.php on line 574
#95 1.160 
#95 1.160 Deprecated: Safe\mssql_connect(): Implicitly marking parameter $servername as nullable is deprecated, the explicit nullable type must be used instead in phar:///tools/.phive/phars/humbug/box-3.16.0.phar/vendor/thecodingmachine/safe/deprecated/mssql.php on line 100
#95 1.160 
#95 1.160 Deprecated: Safe\mssql_connect(): Implicitly marking parameter $username as nullable is deprecated, the explicit nullable type must be used instead in phar:///tools/.phive/phars/humbug/box-3.16.0.phar/vendor/thecodingmachine/safe/deprecated/mssql.php on line 100
#95 1.160 
#95 1.160 Deprecated: Safe\mssql_connect(): Implicitly marking parameter $password as nullable is deprecated, the explicit nullable type must be used instead in phar:///tools/.phive/phars/humbug/box-3.16.0.phar/vendor/thecodingmachine/safe/deprecated/mssql.php on line 100
#95 1.160 
#95 1.160 Deprecated: Safe\mssql_pconnect(): Implicitly marking parameter $servername as nullable is deprecated, the explicit nullable type must be used instead in phar:///tools/.phive/phars/humbug/box-3.16.0.phar/vendor/thecodingmachine/safe/deprecated/mssql.php on line 333
#95 1.160 
#95 1.160 Deprecated: Safe\mssql_pconnect(): Implicitly marking parameter $username as nullable is deprecated, the explicit nullable type must be used instead in phar:///tools/.phive/phars/humbug/box-3.16.0.phar/vendor/thecodingmachine/safe/deprecated/mssql.php on line 333
#95 1.160 
#95 1.160 Deprecated: Safe\mssql_pconnect(): Implicitly marking parameter $password as nullable is deprecated, the explicit nullable type must be used instead in phar:///tools/.phive/phars/humbug/box-3.16.0.phar/vendor/thecodingmachine/safe/deprecated/mssql.php on line 333
#95 1.160 
#95 1.160 Deprecated: Safe\preg_replace(): Implicitly marking parameter $count as nullable is deprecated, the explicit nullable type must be used instead in phar:///tools/.phive/phars/humbug/box-3.16.0.phar/vendor/thecodingmachine/safe/lib/special_cases.php on line 155
#95 1.160 
#95 1.160 Deprecated: Safe�zwrite(): Implicitly marking parameter $length as nullable is deprecated, the explicit nullable type must be used instead in phar:///tools/.phive/phars/humbug/box-3.16.0.phar/vendor/thecodingmachine/safe/generated/bzip2.php on line 84
#95 1.160 
#95 1.160 Deprecated: Safe

[jakzal]

Let's drop this old thing: jakzal/toolbox#553