bump nix version

[yihau]

Problem

There are some changes force us to update our code if we want to bump nix >= 0.27.0

• removed deprecated net API (we're using InetAddr) Nuke deprecated net APIs nix-rust/nix#1861
• removed all features Do not enable any features by default nix-rust/nix#2091
• change behavior for setsockopt Add I/O safety to sockopt and some socket functions nix-rust/nix#1915

I would like to unblock this process by

• remove InetAddr from streamer/src/sendmmsg.rs #557
• remove InetAddr from streamer/src/recvmmsg.rs #558
• bump nix to 0.28.0 #628