Fix misspelling and misgrammar

Signed-off-by: chymy <chang.min1@zte.com.cn>

pkg/apis/authentication/types.go

@@ -118,7 +118,7 @@ type TokenRequest struct {
 
 // TokenRequestSpec contains client provided parameters of a token request.
 type TokenRequestSpec struct {
-	// Audiences are the intendend audiences of the token. A recipient of a
+	// Audiences are the intended audiences of the token. A recipient of a
 	// token must identify themself with an identifier in the list of
 	// audiences of the token, and otherwise should reject the token. A
 	// token issued for multiple audiences may be used to authenticate