* all: run gofumpt
https://github.com/mvdan/gofumpt
The main appeal for me here is that my (and many other peoples')
editors run this on save, so doing a single diff here
keeps other diffs minimal.
* .github/workflows: add gofumpt checker
* Fix grpc.Dial usage in sshpiperd
* fix dns not found
* Update dependencies in go.mod and go.sum files
* Refactor grpc.NewClient to remove unnecessary grpc.WithBlock() option
