Update linter

[rockdaboot]

This PR does:

• update golangci-lint required to rewrite parts of the config file
• update the make target lint to use docker (building with go is no longer supported with v2)
• use make lint in the CI to keep it in sync with local linting (less maintenance)
• amend nolint directives as some linters are no longer available
• trivial code code changes to pass linting

[florianl]

Instead of ever changing various places, I would love if we can wait for a moment, until the minimum supported Go version is Go 1.24.
Starting with Go 1.24 we can just use/manage linters like tools in Go.

Example:

# Install the tool (one time action)
go get -tool honnef.co/go/tools/cmd/staticcheck@v0.5.1
# Use the tool
go tool staticcheck -checks=all ./...

This allows to slim and simplify things in a lot of places.

[rockdaboot]

Instead of ever changing various places, I would love if we can wait for a moment, until the minimum supported Go version is Go 1.24. Starting with Go 1.24 we can just use/manage linters like tools in Go.

Example:

# Install the tool (one time action)
go get -tool honnef.co/go/tools/cmd/staticcheck@v0.5.1
# Use the tool
go tool staticcheck -checks=all ./...

This allows to slim and simplify things in a lot of places.

That possibly a good thing. But can we make this two steps? So get this PR in and whenever we switch to 1.24 and someone has the time, do what you suggest?