storage: fix to PostPolicyV4 doc
Remove statement that option only works for V4, since
these options are only used for V4 signing.
@@ -77,7 +77,6 @@ type PostPolicyV4Options struct {
// Style provides options for the type of URL to use. Options are
// PathStyle (default), BucketBoundHostname, and VirtualHostedStyle. See
// https://cloud.google.com/storage/docs/request-endpoints for details.
- // Only supported for V4 signing.
// Optional.
Style URLStyle
