Fix "statement not reached" warnings (#1518)

https://github.com/ruby/ruby/actions/runs/20486207381/job/58869094401#step:14:641
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/home/runner/work/ruby/ruby/src/gems/src/rdoc/lib/rdoc/generator/template/aliki/_sidebar_pages.rhtml:38:
warning: statement not reached


https://github.com/ruby/ruby/actions/runs/20486207381/job/58869094401#step:14:689
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/home/runner/work/ruby/ruby/src/gems/src/rdoc/lib/rdoc/generator/template/darkfish/_sidebar_pages.rhtml:16:
warning: statement not reached

Author: nobu

lib/rdoc/generator/template/aliki/_sidebar_pages.rhtml

@@ -35,7 +35,7 @@
                 <%= h f.page_name %>
               </a>
             </li>
-            <%- next %>
+            <%- next -%>
           <%- end %>
 
           <li>

lib/rdoc/generator/template/darkfish/_sidebar_pages.rhtml

@@ -13,7 +13,7 @@
     <%- f = files.shift %>
     <%- if files.empty? %>
     <li><a href="<%= rel_prefix %>/<%= h f.path %>"><%= h f.page_name %></a></li>
-      <%- next %>
+      <%- next -%>
     <%- end %>
     <li><details<%= ' open' if dir == n %>><summary><%
     if n == f.page_name