net/http: fix typo in the SameSite docs

Fixes #28244

Change-Id: I3ca36fd513f5543af0c8af254d267254c7d5e803
GitHub-Last-Rev: 83b16fac4e221a249ed036c034367d6f680ae578
GitHub-Pull-Request: golang/go#28302
Reviewed-on: https://go-review.googlesource.com/c/143480Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/net/http/cookie.go

@@ -38,7 +38,7 @@ type Cookie struct {
 
 // SameSite allows a server to define a cookie attribute making it impossible for
 // the browser to send this cookie along with cross-site requests. The main
-// goal is to mitigate the risk of cross-origin information leakage, and provides
+// goal is to mitigate the risk of cross-origin information leakage, and provide
 // some protection against cross-site request forgery attacks.
 //
 // See https://tools.ietf.org/html/draft-ietf-httpbis-cookie-same-site-00 for details.