Milo pubsub: Don't decode properties out of parameters
Milo pubsub: Don't decode properties out of parameters

This isn't used and also isn't always a string (could be an object)

BUG=624960

Review-Url: https://codereview.chromium.org/2980253002

luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go