Fixing import package issue

When #8779 was merged it introduced an issue with windows builds,
which we do not test for in PR CI. This change fixes that problem.

Signed-off-by: Matt Farina <matt@mattfarina.com>
(cherry picked from commit 036832eba9)

cmd/helm/root_windows.go

@@ -16,8 +16,6 @@ limitations under the License.
 
 package main
 
-import "io"
-
 func checkPerms() {
 	// Not yet implemented on Windows. If you know how to do a comprehensive perms
 	// check on Windows, contributions welcomed!