Rename util.go → utils.go

[jandubois]

src/go/guestagent/pkg/utils/util.go has package utils and is in directory utils and should therefore be called utils.go.

Also the package is in one place imported as rdUtils:

$ ag pkg/utils
containerd/events_linux.go
33:	"github.com/containernetworking/plugins/pkg/utils"
36:	rdUtils "github.com/rancher-sandbox/rancher-desktop/src/go/guestagent/pkg/utils"

docker/events.go
33:	"github.com/rancher-sandbox/rancher-desktop/src/go/guestagent/pkg/utils"

iptables/iptables.go
28:	"github.com/rancher-sandbox/rancher-desktop/src/go/guestagent/pkg/utils"

iptables/iptables_test.go
26:	"github.com/rancher-sandbox/rancher-desktop/src/go/guestagent/pkg/utils"

procnet/scanner_linux.go
38:	"github.com/rancher-sandbox/rancher-desktop/src/go/guestagent/pkg/utils"

For consistency it should be imported in all files using the same package name, and the package name should be all lowercase, with no underscore, so e.g. rdutils.