Remove old, unused php-wasm .wasm files (#2846)

## Motivation for the change, related issues

Publishing to NPM is failing with a "Payload too large" error that seems
related to `@php-wasm/node` build size. It turns out that we are
including four unused `.wasm` files that are from older minor PHP
versions.

## Implementation details

Let's remove those modules and retry publishing to NPM.

## Testing Instructions (or ideally a Blueprint)

- CI

Author: brandonpayton