Only use base tags with our expected archs

lib/bob/docker_hub.ex

@@ -49,6 +49,22 @@ defmodule Bob.DockerHub do
     end
   end
 
+  def delete_tag(repo, tag) do
+    url = @dockerhub_url <> "v2/repositories/#{repo}/tags/#{tag}"
+    headers = headers()
+    opts = [:with_body, recv_timeout: 20_000]
+
+    result =
+      Bob.HTTP.retry("DockerHub #{url}", fn ->
+        :hackney.request(:delete, url, headers, "", opts)
+      end)
+
+    case result do
+      {:ok, 204, _headers, _body} -> :ok
+      {:ok, 404, _headers, _body} -> :ok
+    end
+  end
+
   def headers() do
     if token = Application.get_env(:bob, :dockerhub_token) do
       [{"authorization", "JWT #{token}"}]

lib/bob/job/docker_checker.ex

@@ -50,7 +50,8 @@ defmodule Bob.Job.DockerChecker do
     tags =
       ("library/" <> repo)
       |> Bob.DockerHub.fetch_repo_tags()
-      |> Enum.map(&elem(&1, 0))
+      |> Enum.filter(fn {_tag, archs} -> Enum.all?(@archs, &(&1 in archs)) end)
+      |> Enum.map(fn {tag, _archs} -> tag end)
       |> Enum.sort(&(&1 >= &2))
 
     Enum.map(regexes, fn regex ->