Configure HTTPS endpoint (required for BundID registration process #145)

I as a user, would like to verify the integration of the "technischer Durchstich" of the BundID integration and provide certificates.

Problem statement: The connection to the BundID Authentication requires a HTTPS terminated endpoint on port 443 that can be used as an entityID.

Goals: Provide an HTTPS terminated endpoint on port 443 for the address (entityID) https://neo.fitko.dev so that https://gitlab.opencode.de/fitko/matrix-g2x/planning/-/issues/145 can continue

Requirements on it are based on the requirements for the entityId, cf. #145

AC:

• check self serve deployments on dev environment
• add domain neo.fitko.dev
• deploy webserver for given domain
• configure TLS for webserver with either provided TLS certificate or an alternative like let's encrypt
• Check HTTPS endpoint to be valid

References:

Requirements uIDs: Zapuk_80; Zapuk_81