fix(lint-md-action): use showResult() to output detailed lint errors

Author: luojiyin1987

src/lint-md-action.ts

@@ -65,7 +65,7 @@ export class LintMdAction {
 
   showResult() {
     if (this.linter) {
-      this.linter.printOverview()
+      this.linter.showResult()
     }
     return this
   }