Update taste-objects.md

Author: Altair-Bueno

_overviews/scala3-book/taste-objects.md

@@ -27,7 +27,7 @@ For example, this `StringUtils` object contains a small collection of string-rel
 
 ```scala
 object StringUtils:
-  def isNullOrEmpty(s: String): Boolean = s==null || s.trim == ""
+  def isNullOrEmpty(s: String): Boolean = s==null || s.trim.isEmpty
   def leftTrim(s: String): String = s.replaceAll("^\\s+", "")
   def rightTrim(s: String): String = s.replaceAll("\\s+$", "")
 ```