Apply suggestions from code review

Co-authored-by: Philippus Baalman <[email protected]>

Author: Altair-Bueno

_overviews/scala3-book/domain-modeling-tools.md

@@ -219,7 +219,7 @@ Here’s an example of a “string utilities” object that contains a set of me
 object StringUtils:
   def truncate(s: String, length: Int): String = s.take(length)
   def containsWhitespace(s: String): Boolean = s.matches(".*\\s.*")
-  def isNullOrEmpty(s: String): Boolean = s==null || s.trim.isEmpty
+  def isNullOrEmpty(s: String): Boolean = s == null || s.trim.isEmpty
 ```
 
 We can use the object as follows:

_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.isEmpty
+  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+$", "")
 ```
@@ -92,4 +92,3 @@ NOTE: I don’t know if this is worth keeping, but I’m leaving it here as a co
 {% endcomment %}
 
 
-