Change Discord Login Badge to only show if the Discord Auth plugin is loaded,

[Kiro47]

Currently in users/private.html we show the Discord badge if the user has any oauth.id values set. This could be bad in the case of if MLC was also enabled. Instead, we should definitely use the Jinja template to only show it if the discord plugin is enabled and the oauth_id information is present.

For example how MLC handles it:

{% if integrations.mlc() and user.oauth_id %}
    <a href="https://majorleaguecyber.org/u/{{ user.name }}">
        <h3><span class="badge badge-primary">Official</span></h3>
     </a>
{% endif %}

The integrations variable doesn't really offer any support for plugins and the plugins variable itself is also empty for some reason. This may need a bit of research to figure out how exactly to do this.