[php-src] Issue #8864: JSON pretty printing indentation using tabs or double spaces

Issue: https://github.com/php/php-src/issues/8864 Author: timint ### Description The current indentation of pretty printed JSON with json_encode() is using 4 bytes per level. I feel we are lacking the ability to choose intendation type, i.e. for optimization. Example: * Tab (1 bytes) * Two spaces (2 bytes) * Four spaces (4 bytes) Maybe by setting a flag to either: JSON_PRETTY_PRINT JSON_PRETTY_PRINT_TABS JSON_PRETTY_PRINT_DOUBLE_SPACES I know that I can preg_replace() it the way I want. But why waste resources if we could have it at the core.