2023.7.3 rel failed to build with go 1.21.0

[chenrui333]

👋 while upgrading go formula to 1.21.0, we ran into the following build failure

# github.com/quic-go/quic-go/internal/qtls
vendor/github.com/quic-go/quic-go/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

relates to Homebrew/homebrew-core#134468

[chenrui333]

should be good with Homebrew/homebrew-core#140266