[php-src] Issue #7725: README.md steps for reporting bugs should be updated to mention github issues instead of bugs.php.net

Issue: https://github.com/php/php-src/issues/7725 Author: TysonAndre ### Description The README currently says: > Bug fixes **do not** require an RFC but require a bug tracker ticket. Open a > ticket at [bugs.php.net](https://bugs.php.net) and reference the bug id using > #NNNNNN. > > Fix #55371: get_magic_quotes_gpc() throws deprecation warning > > After removing magic quotes, the get_magic_quotes_gpc function caused a > deprecated warning. get_magic_quotes_gpc can be used to detect the > magic_quotes behavior and therefore should not raise a warning at any time. > The patch removes this warning. https://wiki.php.net/rfc/github_issues#proposal changed this: > Bug reports and feature requests are filed on GitHub with custom issue forms. Security issues > point to bugs.php.net instead, because GitHub currently does not support private issue reports. It may be useful to also update the README in older minor versions of php that still get released? https://bugs.php.net/report.php mentions the new steps. ----- Should creating an issue be optional if there's a GitHub PR fixing the bug? ### PHP Version N/A ### Operating System N/A