Use reqwest

Created by: jD91mZM2

This is now possible since tokio is ported.

Don't merge yet, there are still some issues

• I've noticed sometimes tokio things stop working until you reboot. Especially when Ctrl+Cing applications. I have no idea what causes this, but since tokio doesn't really do anything that should be persistent I suspect that either the kernel isn't cleaning up stuff properly somehow or smolnetd is having issues. This should be investigated futher as it can make it unreliable.
• It now depends on openssl (and ca-certificates), because reqwest does not support rustls.