Use squiggly heredocs

This is a feature which was introduced in Ruby 2.3, and makes it much
easier to write readable heredocs.

.rubocop.yml

@@ -61,6 +61,9 @@ Layout/ExtraSpacing:
 Layout/IndentAssignment:
   Enabled: true
 
+Layout/IndentHeredoc:
+  Enabled: true
+
 Layout/IndentationConsistency:
   EnforcedStyle: indented_internal_methods
 

spec/factories/legislations.rb

@@ -124,7 +124,7 @@ FactoryBot.define do
     changelog { "What changed in this version" }
     status { "draft" }
     final_version { false }
-    body { <<-LOREM_IPSUM }
+    body { <<~LOREM_IPSUM }
       Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure dolor in hendrerit in vulputate velit esse molestie consequat, vel illum dolore eu feugiat nulla facilisis at vero eros et accumsan et iusto odio dignissim qui blandit praesent luptatum zzril delenit augue duis dolore te feugait nulla facilisi.
 
       Expetenda tincidunt in sed, ex partem placerat sea, porro commodo ex eam. His putant aeterno interesset at. Usu ea mundi tincidunt, omnium virtute aliquando ius ex. Ea aperiri sententiae duo. Usu nullam dolorum quaestio ei, sit vidit facilisis ea. Per ne impedit iracundia neglegentur. Consetetur neglegentur eum ut, vis animal legimus inimicus id.

spec/models/legislation/draft_version_spec.rb

@@ -20,7 +20,7 @@ describe Legislation::DraftVersion do
   end
 
   def body_markdown
-    <<-BODY_MARKDOWN
+    <<~BODY_MARKDOWN
       # Title 1
 
       Some paragraph.
@@ -41,7 +41,7 @@ BODY_MARKDOWN
   end
 
   def body_html
-    <<-BODY_HTML
+    <<~BODY_HTML
       <h1 id="title-1">Title 1</h1>
 
       <p>Some paragraph.</p>
@@ -64,7 +64,7 @@ BODY_HTML
   end
 
   def toc_html
-    <<-TOC_HTML
+    <<~TOC_HTML
       <ul>
       <li>
       <a href="#title-1">Title 1</a>