Remove duplication around MusicBrainz URL generation

lib/music_library_web/live/collection_live/show.ex

@@ -145,10 +145,6 @@ defmodule MusicLibraryWeb.CollectionLive.Show do
   defp title_segment(:show), do: gettext("Show")
   defp title_segment(:edit), do: gettext("Edit")
 
-  defp musicbrainz_url(record) do
-    "https://musicbrainz.org/release-group/#{record.musicbrainz_id}"
-  end
-
   defp human_datetime(dt) do
     "#{dt.day}/#{dt.month}/#{dt.year}"
   end

lib/music_library_web/live/collection_live/show.html.heex

@@ -103,7 +103,7 @@
           {gettext("MusicBrainz ID")}
         </dt>
         <dd class="mt-1 text-sm flex justify-between leading-6 text-zinc-700 dark:text-zinc-300 sm:col-span-2 sm:mt-0">
-          <a href={musicbrainz_url(@record)}>
+          <a href={MusicBrainz.ReleaseGroup.url(@record.musicbrainz_id)}>
             <code id={"mb-#{@record.musicbrainz_id}"}>{@record.musicbrainz_id}</code>
           </a>
           <button phx-click={

lib/music_library_web/live/wishlist_live/show.ex

@@ -128,10 +128,6 @@ defmodule MusicLibraryWeb.WishlistLive.Show do
   defp title_segment(:show), do: gettext("Show")
   defp title_segment(:edit), do: gettext("Edit")
 
-  defp musicbrainz_url(record) do
-    "https://musicbrainz.org/release-group/#{record.musicbrainz_id}"
-  end
-
   defp human_datetime(dt) do
     "#{dt.day}/#{dt.month}/#{dt.year}"
   end

lib/music_library_web/live/wishlist_live/show.html.heex

@@ -104,7 +104,7 @@
           {gettext("MusicBrainz ID")}
         </dt>
         <dd class="mt-1 text-sm flex justify-between leading-6 text-zinc-700 dark:text-zinc-300 sm:col-span-2 sm:mt-0">
-          <a href={musicbrainz_url(@record)}>
+          <a href={MusicBrainz.ReleaseGroup.url(@record.musicbrainz_id)}>
             <code id={"mb-#{@record.musicbrainz_id}"}>{@record.musicbrainz_id}</code>
           </a>
           <button phx-click={