Update packager#vendored_pin_for

The method now preserves the pin option if it is present.

lib/importmap/packager.rb

@@ -39,12 +39,14 @@ def pin_for(package, url)
   def vendored_pin_for(package, url)
     filename = package_filename(package)
     version  = extract_package_version_from(url)
-
-    if "#{package}.js" == filename
-      %(pin "#{package}" # #{version})
-    else
-      %(pin "#{package}", to: "#{filename}" # #{version})
-    end
+    line_formatted_pin_options = pin_options_for_package(package).except("to").map { |option, value| %(#{option}: #{value.is_a?(String) ? %("#{value}") : value}) }
+    pin_components = [
+      %(pin "#{package}"),
+      (%(to: "#{filename}") unless "#{package}.js" == filename),
+      *line_formatted_pin_options
+    ].compact
+
+    %(#{pin_components.join(", ")} # #{version})
   end
 
   def packaged?(package)

test/packager_test.rb

@@ -54,6 +54,7 @@ def code() "200" end
   test "vendored_pin_for" do
     assert_equal %(pin "react" # @17.0.2), @packager.vendored_pin_for("react", "https://cdn/react@17.0.2")
     assert_equal %(pin "javascript/react", to: "javascript--react.js" # @17.0.2), @packager.vendored_pin_for("javascript/react", "https://cdn/react@17.0.2")
+    assert_equal %(pin "md5", preload: true # @2.1.3), @packager.vendored_pin_for("md5", "https://cdn/md5@2.1.3")
   end
 
   test "pin_options_for_package" do