Update util/oidc/oidc.go

Better phrasing.

Co-authored-by: Blake Pettersson <blake.pettersson@gmail.com>
Signed-off-by: Kevin Lyda <kevin@ie.suberic.net>
Signed-off-by: Kevin Lyda <kevin@lyda.ie>

util/oidc/oidc.go

@@ -288,7 +288,7 @@ func (a *ClientApp) HandleLogin(w http.ResponseWriter, r *http.Request) {
 	returnURL := r.FormValue("return_url")
 	// Check if return_url is valid, otherwise abort processing (see https://github.com/argoproj/argo-cd/pull/4780)
 	if !isValidRedirectURL(returnURL, []string{a.settings.URL}) {
-		log.Errorf("Invalid redirect URL: %s is not a valid per the settings.", returnURL)
+		log.Errorf("Invalid redirect URL: %s is not a valid URL or does not match the URL in settings.", returnURL)
 		http.Error(w, "Invalid redirect URL: the protocol and host (including port) must match and the path must be within allowed URLs if provided", http.StatusBadRequest)
 		return
 	}