Few tweaks and readability refactors

spec/ameba/rule/style/constant_names_spec.cr

@@ -17,7 +17,7 @@ module Ameba
     it "passes if type names are screaming-cased" do
       expect_no_issues subject, <<-CRYSTAL
         LUCKY_NUMBERS     = [3, 7, 11]
-        DOCUMENTATION_URL = "http://crystal-lang.org/docs"
+        DOCUMENTATION_URL = "https://crystal-lang.org/docs"
 
         Int32
 

spec/spec_helper.cr

@@ -286,3 +286,7 @@ end
 def as_nodes(source)
   Ameba::TestNodeVisitor.new(as_node source)
 end
+
+def trailing_whitespace
+  ' '
+end