Update format of the @example YARD doc example

CONTRIBUTING.md

@@ -61,11 +61,8 @@ Include [YARD] style docs for all methods that includes:
 # @return [String]
 # 
 # @example
-#   Faker::Alphanumeric.alpha
-#     #=> "kgdpxlgwjirlqhwhrebvuomdcjjpeqlq" 
-# @example 
-#   Faker::Alphanumeric.alpha(number: 10)
-#     #=> "zlvubkrwga"
+#   Faker::Alphanumeric.alpha #=> "kgdpxlgwjirlqhwhrebvuomdcjjpeqlq" 
+#   Faker::Alphanumeric.alpha(number: 10) #=> "zlvubkrwga"
 #
 # @faker.version next
 def alpha(number: 32)
@@ -107,4 +104,4 @@ a_things:
 * Use the `rake console` task to start a session with Faker loaded.
 * Use `bundle exec yard server -r` to launch the YARD Doc server 
 
-[YARD]: (https://www.rubydoc.info/gems/yard/file/README.md)
+[YARD]: (https://www.rubydoc.info/gems/yard/file/README.md)