* Upgrade golangci-lint to a version built with go 1.21.x. The older
version was a binary version built with go 1.20.x and it was failing
against the newer code built with go 1.21.x
* print the golangci-lint version in each run to see what version of go
it was built with in case there are incompatibilties during the next
upgrade
* remove the linter config skipping over pkg/supervisor entirely and
instead put in an override to ignore the `unused` linter for the
pkg/supervisor testhelpers bits for unsed test functions necessary
to satisfy the test interface.
Jeff Schroeder
tbjump
jumpsiegel