PHP ^8.0 support

After upgrade my php version I'm unable to update composer dependencies due:

- Root composer.json requires assoconnect/graphql-mutation-validator-bundle == 1.0.1.0 -> satisfiable by assoconnect/graphql-mutation-validator-bundle[v1.0.1].
    - assoconnect/graphql-mutation-validator-bundle v1.0.1 requires php ^7.1 -> your php version (8.0.15) does not satisfy that requirement.

Could I open a MR to allow php >= 8.0 version?