[REQ][Slim4] Add package name and version to composer.json

Is your feature request related to a problem? Please describe.

I'm using php-slim4 to generate server code for our API. I want to integrate the generated package in our project with composer using a custom repository of type "path".
Unfortunately the composer.json generated by php-slim4 is missing the required keys name and version.

Describe the solution you'd like

name and version should be added to modules/openapi-generator/src/main/resources/php-slim4-server/composer.mustache like is is in modules/openapi-generator/src/main/resources/php/composer.mustache. That would solve the problem.

{
    "name": "{{gitUserId}}/{{gitRepoId}}",
    {{#artifactVersion}}
    "version": "{{artifactVersion}}",
    {{/artifactVersion}}

   ...
}

Describe alternatives you've considered

At the moment I use a custom composer.mustache when generating the server code. It is just a copy of the repository version with the above lines added. Unfortunately I'll will have to update the file manually every time php-slim4 changes dependencies.

Additional context

The same problem applies when using php-silex and maybe other php-* generators. It would be nice to have more uniform composer.json files among the those generators.

Start with modules/openapi-generator/src/main/resources/php-slim4-server/composer.mustache and compare its Composer metadata with modules/openapi-generator/src/main/resources/php/composer.mustache. Update the Slim4 template so generated composer.json files include the requested name and version fields, then verify the rendered output for the stated package metadata.