🚀 Enhancement: Add environment variable _APP_USE_SELF_SIGNED_TLS

### 🔖 Enhancement description You should add an environment variable for users that are self-hosting appwrite and don't use the default Ports 80 and 443 on their host machines. It would be very useful to have an environment variable that just tells the appwrite instance that it's served over HTTPS and should therefore use https in the redirect_uri. ### 🎤 Pitch In my use-case, it would help me successfully implement OAuth Google Authentication. From appwrite documentation: > Currently, Appwrite is using the [ACME](https://letsencrypt.org/docs/client-options/) HTTP challenge to issue an TLS certificate. This forces us to generate certificates for port 443 when the challenge itself is performed on port 80. At this point, other ports will not work. To overcome this limit, you can set Appwrite on a separate sub-domain or use your own certificate or proxy server in front of Appwrite. So I was using Caddy as reverse proxy to secure the connections to appwrite's port 80. Everything seems to work fine, the admin dashboard is served securely over https. However, when I then try to use Google Authentication, the setup assistant tells me to add the HTTPS url to redirect_uris in Google Cloud Console:  When calling createOauthSession() however, the HTTP redirect_uri is used:  It would be very useful to have an environment variable that just tells the appwrite instance that it's served over HTTPS and should therefore use https in the redirect_uri. Please also refer to [this Discord thread](https://discord.com/channels/564160730845151244/1264501642749808713) for further information. ### 👀 Have you spent some time to check if this issue has been raised before? - [X] I checked and didn't find similar issue ### 🏢 Have you read the Code of Conduct? - […