Revert "FIX: trim trailing slash from topic links"

This reverts commit 993f847a2c.

There is an edge case where the link click redirect fails when the URL has trailing slash. Need to figure out a better fix for this.

app/models/topic_link.rb

@@ -205,7 +205,7 @@ SQL
       reflected_post = Post.find_by(topic_id: topic_id, post_number: post_number.to_i)
     end
 
-    url = url[0...TopicLink.max_url_length]&.chomp("/")
+    url = url[0...TopicLink.max_url_length]
     return nil if parsed && parsed.host && parsed.host.length > TopicLink.max_domain_length
 
     unless TopicLink.exists?(topic_id: post.topic_id, post_id: post.id, url: url)

spec/models/topic_link_spec.rb

@@ -41,7 +41,7 @@ describe TopicLink do
 
     it 'works' do
       expect(topic.topic_links.pluck(:url)).to contain_exactly(
-        "http://a.com",
+        "http://a.com/",
         "https://b.com/b",
         "//b.com/#{'a' * 500}"[0...TopicLink.max_url_length]
       )