added, PHP_LEGACY_OPENSSL (Fix for OpenSSL 3)

[erikn69]

Description

This fix signing errors, or reading errors in electronic signatures (PHP 8.2, 8.3).
Legacy is only added when OpenSSL 3 is used and PHP_LEGACY_OPENSSL=true

Since OpenSSL 3, some ciphers are not available unless users configure some openssl.cnf file ... so allowing this would unbreak applications depending on this feature.
...the .p12 file uses the quite common RC2-40-CBC cipher suite and let the rest of PHP without legacy provider

php/php-src#12369 (comment)
php/php-src#12128 (comment)

Types of Changes

• Bug fix (non-breaking change which fixes an issue).
• [] New feature (non-breaking change which adds functionality).
• [] Breaking change (fix or feature that would cause existing functionality to not work as expected).

Definition of Done Checklist:

• I've read the Contribution Guide.
• [] I've updated the documentation. (refer to this for how to do so).
• I enjoyed my time contributing and making developer's life easier :)