Expose php 8.2 `ENCAPS_VAR_DOLLAR_CURLY*` flags in ast\flags

[TysonAndre]

https://wiki.php.net/rfc/deprecate_dollar_brace_string_interpolation - php 8.2 deprecated ${} in favor of {$

From php-src Zend/zend_compile.c

This is similar to how for php-ast php 7.4 introduced PARENTHESIZED_CONDITIONAL(combinable) on AST_CONDITIONAL nodes (cond ? true : false)

// Used by ast\AST_CONDITIONAL (combinable), since PHP 7.4
ast\flags\PARENTHESIZED_CONDITIONAL