Add a specific class to "Inspect GraphQL query" button and apply styling to it

[sasanikolic90]

Currently, we target .graphql-twig-debug-wrapper input[type="submit"] which breaks other input fields on the page, as graphql-twig-debug-wrapper wraps the whole content of the page.

I suggest we add a specific class to the button and apply styling to it.

[pmelab]

This is related to the graphql_twig module, and was fixed in drupal-graphql/graphql-twig@45a9fa3