Alternative api endpoint should have other ports

[mkevinstever]

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Hello, Proton VPN team: Presently, if the primary ProtonVPN API endpoint is inaccessible due to blocking, the application attempts to connect through alternative available endpoints. However, upon examining the backup endpoint, a critical issue emerges: it solely utilizes port 443 for HTTPS connections and lacks additional ports. Consequently, in restricted environments, users may encounter difficulties in establishing a successful connection to the API server, significantly impairing the functionality of the application. To address this concern, it's imperative to include a non-standard HTTPS port for the backup endpoint.

Thanks.