fix(Oauth2): incorrect RFC reference in OAuth2 plugin schema (#14371)

Author: dingjiayi

kong/plugins/oauth2/schema.lua

@@ -24,10 +24,10 @@ return {
           { mandatory_scope = { description = "An optional boolean value telling the plugin to require at least one `scope` to be authorized by the end user.", type = "boolean", default = false, required = true }, },
           { provision_key = { description = "The unique key the plugin has generated when it has been added to the Service.", type = "string", unique = true, auto = true, required = true, encrypted = true }, }, -- encrypted = true is a Kong Enterprise Exclusive feature. It does nothing in Kong CE
           { token_expiration = { description = "An optional integer value telling the plugin how many seconds a token should last, after which the client will need to refresh the token. Set to `0` to disable the expiration.", type = "number", default = 7200, required = true }, },
-          { enable_authorization_code = { description = "An optional boolean value to enable the three-legged Authorization Code flow (RFC 6742 Section 4.1).", type = "boolean", default = false, required = true }, },
-          { enable_implicit_grant = { description = "An optional boolean value to enable the Implicit Grant flow which allows to provision a token as a result of the authorization process (RFC 6742 Section 4.2).", type = "boolean", default = false, required = true }, },
-          { enable_client_credentials = { description = "An optional boolean value to enable the Client Credentials Grant flow (RFC 6742 Section 4.4).", type = "boolean", default = false, required = true }, },
-          { enable_password_grant = { description = "An optional boolean value to enable the Resource Owner Password Credentials Grant flow (RFC 6742 Section 4.3).", type = "boolean", default = false, required = true }, },
+          { enable_authorization_code = { description = "An optional boolean value to enable the three-legged Authorization Code flow (RFC 6749 Section 4.1).", type = "boolean", default = false, required = true }, },
+          { enable_implicit_grant = { description = "An optional boolean value to enable the Implicit Grant flow which allows to provision a token as a result of the authorization process (RFC 6749 Section 4.2).", type = "boolean", default = false, required = true }, },
+          { enable_client_credentials = { description = "An optional boolean value to enable the Client Credentials Grant flow (RFC 6749 Section 4.4).", type = "boolean", default = false, required = true }, },
+          { enable_password_grant = { description = "An optional boolean value to enable the Resource Owner Password Credentials Grant flow (RFC 6749 Section 4.3).", type = "boolean", default = false, required = true }, },
           { hide_credentials = { description = "An optional boolean value telling the plugin to show or hide the credential from the upstream service.", type = "boolean", default = false, required = true }, },
           { accept_http_if_already_terminated = { description = "Accepts HTTPs requests that have already been terminated by a proxy or load balancer.", type = "boolean", default = false, required = true }, },
           { anonymous = { description = "An optional string (consumer UUID or username) value to use as an “anonymous” consumer if authentication fails.", type = "string" }, },