Bump php in /implementations/php-opis-json-schema

Bumps php from 8.3-fpm-alpine to 8.4-fpm-alpine.

---
updated-dependencies:
- dependency-name: php
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

implementations/php-opis-json-schema/Dockerfile

@@ -7,7 +7,7 @@ RUN composer install --no-dev --no-scripts --no-interaction --prefer-dist --opti
 COPY bowtieJsonSchema.php .
 RUN composer dump-autoload --no-dev --optimize --classmap-authoritative
 
-FROM php:8.3-fpm-alpine
+FROM php:8.4-fpm-alpine
 
 WORKDIR /usr/src/myapp