perf: use polymophism instead duck test

src/parser/output-token.ts

@@ -1,8 +1,21 @@
 import DelimitedToken from './delimited-token'
+import Token from './token'
+import { NormalizedFullOptions } from '../liquid-options'
 
 export default class OutputToken extends DelimitedToken {
-  constructor (raw: string, value: string, input: string, line: number, pos: number, file?: string) {
-    super(raw, value, input, line, pos, file)
+  constructor (
+    raw: string,
+    value: string,
+    input: string,
+    line: number,
+    pos: number,
+    options: NormalizedFullOptions,
+    file?: string
+  ) {
+    super(raw, value, input, line, pos, options.trimOutputLeft, options.trimOutputRight, file)
     this.type = 'output'
   }
+  static is (token: Token): token is OutputToken {
+    return token.type === 'output'
+  }
 }