Update ext-php-rs

[shyim]

Hey,

the ext-php-rs version is right now pinned. https://github.com/danog/php-tokio/blob/master/Cargo.toml#L12

Is there any specific reason? 🤔 I am rust newbie and running into problems with ```
= note: perhaps two different versions of crate ext_php_rs are being used?

and found that for this: https://users.rust-lang.org/t/compilation-error-because-two-different-versions-of-crate-are-being-used/37775/3