Remove root-only options from composer.json?

Problem/Motivation

looking at composer.json of this module, it seems there are some root-only options that will have no effect and may therefore be removed from composer.json

These options are:

• require-dev
• repositories
• prefer-stable
• minimum-stability

See https://getcomposer.org/doc/04-schema.md for reference on this.

Acceptance Criteria

Testing steps