GlFormRadio emits events twice

Description

Both the @change and @input events on GlFormRadio are emitted twice whenever they are triggered.

How to reproduce

1. Check out a demo branch: https://gitlab.com/gitlab-org/gitlab-ui/-/tree/dpisek-form-radio-events
2. yarn start
3. Navigate to http://localhost:9001/?path=/story/base-form-form-radio--default
4. Check the output below the radio buttons

Suggested fix

Remove v-on="$listeners from https://gitlab.com/gitlab-org/gitlab-ui/-/blob/main/src/components/base/form/form_radio/form_radio.vue#L41

Note: When using v-on="$listeners" but not adding explicit emits for @change and @input it works in the browser, but not within the specs.