Don't re-push every tag

Don’t re-push every tag

diff --git a/Rakefile b/Rakefile
index 9cee614..2a54399 100644
--- a/Rakefile
+++ b/Rakefile
@@ -58,6 +58,6 @@ namespace :docker do
   desc "Publish a new docker image"
   task publish: :build do
     sh "docker push discourse/mobystash:#{tag}"
-    sh "docker push discourse/mobystash"
+    sh "docker push discourse/mobystash:latest"
   end
 end

GitHub sha: 5d4b80ed