workflows/publish-commit-bottles: fix org fork comment

It looks like GitHub finally sets `maintainer_can_modify` to `false` for
org forks, so we've been mistakenly been showing the wrong message to
PRs from org forks. See #192146 for an example.

Let's fix that.

.github/workflows/publish-commit-bottles.yml

@@ -173,7 +173,7 @@ jobs:
              [[ "$bottles" = "false" ]]
           then
             exit 0
-          elif "$pushable"
+          elif "$pushable" || [[ "$fork_type" = "Organization" ]]
           then
             MESSAGE="$ORG_FORK_MESSAGE"
           else