fix golangci-lint check error

[neo-liang-sap]

What this PR does / why we need it:
fix golangci-lint check error
Which issue(s) this PR fixes:
Fixes #434

Special notes for your reviewer:

Release note:

fix some golangci-lint check error

[dansible]

Thanks Neo 👍 This solves the original linting issues but it seems we have a few more from running the check:

pkg/cmd/info.go:86:4: S1038: should use fmt.Fprintf instead of fmt.Fprintln(fmt.Sprintf(...)) (but don't forget the newline) (gosimple)
			fmt.Fprintln(w, fmt.Sprintf("%s\t%s\t%s\t%s", "----", "-----", "------", "----------"))
			^
pkg/cmd/info.go:87:4: S1038: should use fmt.Fprintf instead of fmt.Fprintln(fmt.Sprintf(...)) (but don't forget the newline) (gosimple)
			fmt.Fprintln(w, fmt.Sprintf("%s\t%d\t%d\t%d", "TOTAL", len(shootList.Items), len(shootList.Items)-hibernatedShootsCount-unscheduled, hibernatedShootsCount))
			^
pkg/cmd/info.go:88:4: S1038: should use fmt.Fprintf instead of fmt.Fprintln(fmt.Sprintf(...)) (but don't forget the newline) (gosimple)
			fmt.Fprintln(w, fmt.Sprintf("%s\t%d", "Unscheduled", unscheduled))

Do you want to address them with this issue/PR or open a new one for these?

[neo-liang-sap]

i will fix these issues together in this PR - thanks for pointing out!
-Neo