[v9.3.x] Oauth: Remove extra decoding of redirect url (#60878)

Oauth: Remove extra decoding of redirect url (#60875)

Oauth: remove extra decoding of redirect cookie url
(cherry picked from commit 5b4e1ee6fc)

Co-authored-by: Karl Persson <kalle.persson@grafana.com>

pkg/api/login_oauth.go

@@ -9,7 +9,6 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
-	"net/url"
 
 	"golang.org/x/oauth2"
 
@@ -258,7 +257,7 @@ func (hs *HTTPServer) OAuthLogin(ctx *models.ReqContext) {
 	hs.HooksService.RunLoginHook(&loginInfo, ctx)
 	metrics.MApiLoginOAuth.Inc()
 
-	if redirectTo, err := url.QueryUnescape(ctx.GetCookie("redirect_to")); err == nil && len(redirectTo) > 0 {
+	if redirectTo := ctx.GetCookie("redirect_to"); len(redirectTo) > 0 {
 		if err := hs.ValidateRedirectTo(redirectTo); err == nil {
 			cookies.DeleteCookie(ctx.Resp, "redirect_to", hs.CookieOptionsFromCfg)
 			ctx.Redirect(redirectTo)