XFA - Default background in rectangle is white

- Fix a typo in order to open the pdf in issue #13679
  - After fixing the fill default color there wer some regressions because of z-index
    and when fixing z-index there were some regressions because of borders
  - So fix the borders rendering.

src/core/xfa/config.js

@@ -171,7 +171,7 @@ class BehaviorOverride extends ContentObject {
       this[$content]
         .trim()
         .split(/\s+/)
-        .filter(x => !!x && x.include(":"))
+        .filter(x => x.includes(":"))
         .map(x => x.split(":", 2))
     );
   }