The storage library that gcs depends on transitively imports grpc in
version 1.50.0, which is vulnerable to GHSA-m425-mq94-257g.

While this is a server-side vulnerability, therefore the package is not
directly vulnerable (nor its clients), this dependency still causes
advisories to be produced against this package, so we update those now.

Sicne we require go v1.19 now at minimum, we cannot run tests on go
v1.17 or v1.18 anymore.

Since there are more recent versions of Go available as well, we start
testing the packages on those versions in addition to 1.19.