fix(sfc): only include legacy decorator parser plugin when new plugin is not used

packages/compiler-sfc/src/compileScript.ts

@@ -126,7 +126,12 @@ export function compileScript(
       )
   }
   if (options.babelParserPlugins) plugins.push(...options.babelParserPlugins)
-  if (isTS) plugins.push('typescript', 'decorators-legacy')
+  if (isTS) {
+    plugins.push('typescript')
+    if (!plugins.includes('decorators')) {
+      plugins.push('decorators-legacy')
+    }
+  }
 
   if (!scriptSetup) {
     if (!script) {