fix: fix linting of tsx script in .vue file (#3097)

Author: lihuanji

packages/@vue/cli-plugin-typescript/lib/tslint.js

@@ -49,7 +49,7 @@ module.exports = function lint (args = {}, api, silent) {
         before: content.slice(0, script.start),
         after: content.slice(script.end)
       })
-      return script.content
+      return script
     }
   }
 
@@ -61,8 +61,9 @@ module.exports = function lint (args = {}, api, silent) {
     const getSourceFile = program.getSourceFile
     program.getSourceFile = function (file, languageVersion, onError) {
       if (isVueFile(file)) {
-        const script = parseTSFromVueFile(file) || ''
-        return ts.createSourceFile(file, script, languageVersion, true)
+        const { content, lang = 'js' } = parseTSFromVueFile(file) || { content: '', lang: 'js' }
+        const contentLang = ts.ScriptKind[lang.toUpperCase()];
+        return ts.createSourceFile(file, content, languageVersion, true, contentLang)
       } else {
         return getSourceFile.call(this, file, languageVersion, onError)
       }