Handle when the URL has interpolation: use source not str_content

- We see this a lot in real Casks.

Library/Homebrew/rubocops/cask/url.rb

@@ -24,7 +24,7 @@ module RuboCop
         def on_url_stanza(stanza)
           return if stanza.stanza_node.block_type?
 
-          url_string = stanza.stanza_node.first_argument.str_content
+          url_stanza = stanza.stanza_node.first_argument
           hash_node = stanza.stanza_node.last_argument
           return unless hash_node.hash_type?
 
@@ -42,7 +42,7 @@ module RuboCop
             end
 
             # Skip if the URL and the verified value are the same.
-            next if value_node.str_content == url_string.delete_prefix("https://").delete_prefix("http://")
+            next if value_node.source == url_stanza.source.gsub(%r{^"https?://}, "\"")
             # Skip if the verified value ends with a slash.
             next if value_node.str_content.end_with?("/")
 

Library/Homebrew/test/rubocops/cask/url_spec.rb

@@ -175,6 +175,20 @@ describe RuboCop::Cop::Cask::Url do
     include_examples "does not report any offenses"
   end
 
+  context "when the url has interpolation in it and the verified url ends with a /" do
+    let(:source) do
+      <<~CASK
+        cask "foo" do
+          version "1.2.3"
+          url "https://example.com/download/foo-v\#{version}.dmg",
+              verified: "example.com/download/"
+        end
+      CASK
+    end
+
+    include_examples "does not report any offenses"
+  end
+
   context "when the url 'verified' value has a path component that doesn't end with a /" do
     let(:source) do
       <<~CASK