Support golang 1.21 by upgrading libp2p

[arner]

The currently used version of go-libp2p (v0.27.8) does not support go 1.21.

When building FSC, it leads to the following error:

# github.com/quic-go/quic-go/internal/qtls
../../go/pkg/mod/github.com/quic-go/[email protected]/internal/qtls/go121.go:5:13: cannot use "The version of quic-go you're using can't be built on Go 1.21 yet. For more details, please see https://github.com/quic-go/quic-go/wiki/quic-go-and-Go-versions." (untyped string constant "The version of quic-go you're using can't be built on Go 1.21 yet. F...) as int value in variable declaration

This is fixed in a recent version of go-libp2p: libp2p/go-libp2p#2497. Upgrading to v0.30.0 should resolve the issue and allow FSC to be built on golang v1.21.0.